(maint) Quote Ruby symbols in .sync.yml for PDK 3.4.0 compatibility

Due to stricter YAML parsing rules in Ruby 3.2.5 (used by PDK 3.4.0),
unquoted Ruby symbols in .sync.yml cause parsing errors. This updates
all Ruby symbols to be properly quoted strings (e.g. ':development'
instead of :development).

The error encountered was:

```bash
Psych::DisallowedClass: Tried to load unspecified class: Symbol
  from psych/class_loader.rb:99:in `find'
```

This change allows the module to be properly updated using PDK 3.4.0
while maintaining the same functionality.

Signed-off-by: Gavin Didrichsen <[email protected]>

Author: gavindidrichsen

.sync.yml

@@ -1,19 +1,19 @@
 ---
 Gemfile:
   required:
-    :development:
+    ':development':
       - gem: bolt
         version: '>= 3.10.0'
   optional:
-    :development:
+    ':development':
       - gem: github_changelog_generator
         version: 1.16.4  # Pinned to latest bug fix version
       - gem: octokit
         version: 4.21.0  # Locked due to https://github.com/octokit/octokit.rb/issues/1391
       # The Faraday requirements in orchestrator_client 0.7.1 causes Bundler to
       # resolve the dependency in unexpected ways and causes issues in CI
       - gem: orchestrator_client
-        version: < 0.7.1
+        version: '< 0.7.1'
 Rakefile:
   changelog_since_tag: 2.5.0
   default_disabled_lint_checks:
@@ -23,7 +23,7 @@ Rakefile:
     - PuppetSyntax.exclude_paths = ["plans/**/*.pp", "spec/acceptance/**/plans/**/*.pp",
       "vendor/**/*"]
 spec/spec_helper.rb:
-  mock_with: :rspec
+  mock_with: ':rspec'
 .gitignore:
   paths:
     - .rerun.json