docs: fix version string typo in CRD documentation

Fix inconsistency in the introducing_new_crds.rst documentation where
the text referenced 'v2alpha.BGPPoolName' but the code example used
'v2alpha1.BGPPoolName'. The text was missing the '1' in the version
prefix.

Signed-off-by: Akanksha Trehun <akankshatrehun@gmail.com>

Author: magic-peach

Documentation/contributing/development/introducing_new_crds.rst

@@ -292,7 +292,7 @@ Your new CRDs must be installed into Kubernetes. This is controlled in
 the ``pkg/k8s/synced/crd.go`` file.
 
 Here is an example diff which installs the CRDs ``v2alpha1.BGPPName``
-and ``v2alpha.BGPPoolName``:
+and ``v2alpha1.BGPPoolName``:
 
 .. code-block:: diff