Ensure default customization of Chart dependencies (#748)

### Description of the change

This adds unittests for the default configuration of our dependencies.

### Benefits

We are able to detect changes in upstream Charts for those settings.

### Applicable issues

- fixes #409

### Additional information

I merged existing unittests with the new ones for `postgresql-ha` and `postgresql`.
However, I decided to not do this for `redis-cluster` and `redis`, because the existing tests[^1] also ensure how the Chart behaves when both redis dependencies are disabled. It didn't felt right to split those files.

### Checklist

- [x] Templating unittests are added

Signed-off-by: justusbunsi <sk.bunsenbrenner@gmail.com>

[^1]: e733287dc2/unittests/config/cache-config.yaml, e733287dc2/unittests/config/queue-config.yaml, e733287dc2/unittests/config/session-config.yaml

Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/748
Co-authored-by: justusbunsi <sk.bunsenbrenner@gmail.com>
Co-committed-by: justusbunsi <sk.bunsenbrenner@gmail.com>

Makefile

@@ -9,7 +9,7 @@ readme: prepare-environment
 
 .PHONY: unittests
 unittests:
-	helm unittest --strict -f 'unittests/**/*.yaml' -f 'unittests/dependency-major-image-check.yaml' -f 'unittests/values-conflicting-checks.yaml' ./
+	helm unittest --strict -f 'unittests/**/*.yaml' -f 'unittests/values-conflicting-checks.yaml' ./
 
 .PHONY: helm
 update-helm-dependencies: