fix(tests): quote regex patterns in matchRegex assertions

Fix YAML syntax errors where patterns containing colons need to be quoted
to avoid being interpreted as YAML mapping values.

Affected files:
- deployment_image_test.yaml
- regression_defaults_test.yaml

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: Aleksei Sviridkin <f@lex.la>

charts/jellyfin/tests/regression_defaults_test.yaml

@@ -39,7 +39,7 @@ tests:
     asserts:
       - matchRegex:
           path: spec.template.spec.containers[0].image
-          pattern: ^jellyfin/jellyfin:
+          pattern: "^jellyfin/jellyfin:"
 
   - it: should use IfNotPresent pullPolicy by default
     template: deployment.yaml