docs: patch Poetry build instructions

Some parts of the documentation referring to Poetry provides incorrect
build instructions and has some minor formatting errors. Reformat the
bits that require formatting, and fix the build instructions. These
were originally part of the patch stack that added Poetry support but
were accidentally reverted prior to merge.

Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
Change-Id: I336d3a7bbe99f75262430ae436f8ebc2cb050d2c
diff --git a/docs/getting_started/prerequisites.rst b/docs/getting_started/prerequisites.rst
index f30216a..bf10ecf 100644
--- a/docs/getting_started/prerequisites.rst
+++ b/docs/getting_started/prerequisites.rst
@@ -100,10 +100,10 @@
 
 - Poetry >= 1.3.2
 
-  Required for managing Python dependencies, this will allow you to reliably
-  reproduce a Python environment to build documentation and run analysis tools.
-  Most importantly, it ensures your system environment will not be affected by
-  dependencies in the Python scripts.
+   Required for managing Python dependencies, this will allow you to reliably
+   reproduce a Python environment to build documentation and run analysis tools.
+   Most importantly, it ensures your system environment will not be affected by
+   dependencies in the Python scripts.
 
 Package Installation (Linux)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^