CI: github actions: add OpenTracing builds

let us add OpenTracing module to "all features" builds

(cherry picked from commit 75c95aa649e1217d885d31a1053a508301167b94)
Signed-off-by: William Lallemand <wlallemand@haproxy.org>
diff --git a/.github/matrix.py b/.github/matrix.py
index 116ea98..91ba34b 100644
--- a/.github/matrix.py
+++ b/.github/matrix.py
@@ -71,6 +71,10 @@
             "CC": CC,
             "FLAGS": [
                 "USE_ZLIB=1",
+                "USE_OT=1",
+                "OT_INC=${HOME}/opt/include",
+                "OT_LIB=${HOME}/opt/lib",
+                "OT_RUNPATH=1",
                 "USE_PCRE=1",
                 "USE_PCRE_JIT=1",
                 "USE_LUA=1",
@@ -142,6 +146,10 @@
         "FLAGS": get_asan_flags(CC)
         + [
             "USE_ZLIB=1",
+            "USE_OT=1",
+            "OT_INC=${HOME}/opt/include",
+            "OT_LIB=${HOME}/opt/lib",
+            "OT_RUNPATH=1",
             "USE_PCRE=1",
             "USE_PCRE_JIT=1",
             "USE_LUA=1",
diff --git a/.github/workflows/vtest.yml b/.github/workflows/vtest.yml
index fbf2d9d..6d6d35e 100644
--- a/.github/workflows/vtest.yml
+++ b/.github/workflows/vtest.yml
@@ -68,6 +68,9 @@
     - name: Install SSL ${{ matrix.ssl }}
       if: ${{ matrix.ssl && matrix.ssl != 'stock' }}
       run: env ${{ matrix.ssl }} scripts/build-ssl.sh
+    - name: Install OpenTracing libs
+      if: ${{ contains(matrix.FLAGS, 'USE_OT=1') }}
+      run: scripts/build-ot.sh
     - name: Build WURFL
       if: ${{ contains(matrix.FLAGS, 'USE_WURFL=1') }}
       run: make -C addons/wurfl/dummy