REGTESTS: Fix required versions for several scripts

The following scripts require HAProxy 2.4 :

 * cache/caching_rules.vtc
 * cache/post_on_entry.vtc
 * cache/vary.vtc
 * checks/1be_40srv_odd_health_checks.vtc
 * checks/40be_2srv_odd_health_checks.vtc
 * checks/4be_1srv_health_checks.vtc
 * converter/fix.vtc
 * converter/mqtt.vtc
 * http-messaging/protocol_upgrade.vtc
 * http-messaging/websocket.vtc
 * http-set-timeout/set_timeout.vtc
 * log/log_uri.vtc

However it may change is features are backported.
diff --git a/reg-tests/cache/caching_rules.vtc b/reg-tests/cache/caching_rules.vtc
index ccbead7..c20a720 100644
--- a/reg-tests/cache/caching_rules.vtc
+++ b/reg-tests/cache/caching_rules.vtc
@@ -2,7 +2,7 @@
 # A response will not be cached unless it has an explicit age (Cache-Control max-age of s-maxage, Expires) or a validator (Last-Modified, or ETag)
 # A response will not be cached either if it has an Age header that is either invalid (should be an integer) or greater than its max age.
 
-#REQUIRE_VERSION=1.9
+#REQUIRE_VERSION=2.4
 
 feature ignore_unknown_macro
 
diff --git a/reg-tests/cache/post_on_entry.vtc b/reg-tests/cache/post_on_entry.vtc
index 2b807f6..db6414e 100644
--- a/reg-tests/cache/post_on_entry.vtc
+++ b/reg-tests/cache/post_on_entry.vtc
@@ -1,6 +1,6 @@
 varnishtest "A successful unsafe method (POST for instance) on a cached entry must disable it."
 
-#REQUIRE_VERSION=2.3
+#REQUIRE_VERSION=2.4
 
 feature ignore_unknown_macro
 
diff --git a/reg-tests/cache/vary.vtc b/reg-tests/cache/vary.vtc
index fc2c445..f3425d0 100644
--- a/reg-tests/cache/vary.vtc
+++ b/reg-tests/cache/vary.vtc
@@ -1,6 +1,6 @@
 varnishtest "Vary support"
 
-#REQUIRE_VERSION=2.3
+#REQUIRE_VERSION=2.4
 
 feature ignore_unknown_macro
 
diff --git a/reg-tests/checks/1be_40srv_odd_health_checks.vtc b/reg-tests/checks/1be_40srv_odd_health_checks.vtc
index 7e8e431..bd07d88 100644
--- a/reg-tests/checks/1be_40srv_odd_health_checks.vtc
+++ b/reg-tests/checks/1be_40srv_odd_health_checks.vtc
@@ -6,7 +6,7 @@
 # The first health-checks passed tests are checked for all these servers
 # thanks to syslog messages.
 
-#REQUIRE_VERSION=1.8
+#REQUIRE_VERSION=2.4
 #EXCLUDE_TARGETS=freebsd
 #REGTEST_TYPE=slow
 
diff --git a/reg-tests/checks/40be_2srv_odd_health_checks.vtc b/reg-tests/checks/40be_2srv_odd_health_checks.vtc
index fb22959..d1cabbc 100644
--- a/reg-tests/checks/40be_2srv_odd_health_checks.vtc
+++ b/reg-tests/checks/40be_2srv_odd_health_checks.vtc
@@ -1,7 +1,7 @@
 varnishtest "Health-checks"
 feature ignore_unknown_macro
 
-#REQUIRE_VERSION=1.8
+#REQUIRE_VERSION=2.4
 #EXCLUDE_TARGETS=freebsd,osx,generic
 #REGTEST_TYPE=slow
 
diff --git a/reg-tests/checks/4be_1srv_health_checks.vtc b/reg-tests/checks/4be_1srv_health_checks.vtc
index b8bd105..2252490 100644
--- a/reg-tests/checks/4be_1srv_health_checks.vtc
+++ b/reg-tests/checks/4be_1srv_health_checks.vtc
@@ -1,7 +1,7 @@
 varnishtest "Health-check test"
 feature ignore_unknown_macro
 
-#REQUIRE_VERSION=1.8
+#REQUIRE_VERSION=2.4
 #EXCLUDE_TARGETS=freebsd
 #REGTEST_TYPE=slow
 
diff --git a/reg-tests/converter/fix.vtc b/reg-tests/converter/fix.vtc
index 6d6ea6f..8bddc4d 100644
--- a/reg-tests/converter/fix.vtc
+++ b/reg-tests/converter/fix.vtc
@@ -1,5 +1,5 @@
 varnishtest "fix converters Test"
-#REQUIRE_VERSION=2.3
+#REQUIRE_VERSION=2.4
 
 feature ignore_unknown_macro
 
diff --git a/reg-tests/converter/mqtt.vtc b/reg-tests/converter/mqtt.vtc
index 7d179ab..15d03ed 100644
--- a/reg-tests/converter/mqtt.vtc
+++ b/reg-tests/converter/mqtt.vtc
@@ -1,5 +1,5 @@
 varnishtest "mqtt converters Test"
-#REQUIRE_VERSION=2.3
+#REQUIRE_VERSION=2.4
 
 feature ignore_unknown_macro
 
diff --git a/reg-tests/http-messaging/protocol_upgrade.vtc b/reg-tests/http-messaging/protocol_upgrade.vtc
index 18e5afe..753aafe 100644
--- a/reg-tests/http-messaging/protocol_upgrade.vtc
+++ b/reg-tests/http-messaging/protocol_upgrade.vtc
@@ -8,6 +8,8 @@
 
 feature ignore_unknown_macro
 
+#REQUIRE_VERSION=2.4
+
 # http/1.1 server
 server srv_h1 {
 	rxreq
diff --git a/reg-tests/http-messaging/websocket.vtc b/reg-tests/http-messaging/websocket.vtc
index 82f5e8b..576c89d 100644
--- a/reg-tests/http-messaging/websocket.vtc
+++ b/reg-tests/http-messaging/websocket.vtc
@@ -12,6 +12,8 @@
 
 feature ignore_unknown_macro
 
+#REQUIRE_VERSION=2.4
+
 # valid websocket server
 server s1 {
 	rxreq
diff --git a/reg-tests/http-set-timeout/set_timeout.vtc b/reg-tests/http-set-timeout/set_timeout.vtc
index 4847b80..6840164 100644
--- a/reg-tests/http-set-timeout/set_timeout.vtc
+++ b/reg-tests/http-set-timeout/set_timeout.vtc
@@ -2,6 +2,8 @@
 
 feature ignore_unknown_macro
 
+#REQUIRE_VERSION=2.4
+
 server srv_h1 -repeat 3 {
     rxreq
     txresp
diff --git a/reg-tests/log/log_uri.vtc b/reg-tests/log/log_uri.vtc
index 00f0553..b5a5753 100644
--- a/reg-tests/log/log_uri.vtc
+++ b/reg-tests/log/log_uri.vtc
@@ -1,6 +1,8 @@
 varnishtest "Verify logging of relative/absolute URI path"
 feature ignore_unknown_macro
 
+#REQUIRE_VERSION=2.4
+
 server s1 {
     rxreq
     txresp