Fix regex escaping in Lab 1 Ollama version extraction

In the YAML folded block scalar, \\. was passed literally to
regex_search as \., so it never matched valid semver strings like
0.21.1. Use \. instead so the dot is matched correctly.

ansible/roles/lab1_assets/tasks/main.yml

@@ -17,7 +17,7 @@
     courseware_lab1_ollama_semver: >-
       {{
         courseware_lab1_ollama_version.stdout
-        | regex_search('[0-9]+\\.[0-9]+\\.[0-9]+')
+        | regex_search('[0-9]+\.[0-9]+\.[0-9]+')
         | default('')
       }}