docs: Add postgreSqlInitContainer values to README

[lindhe]

Description of the change

This change documents the value field nextcloud.postgreSqlInitContainer.securityContext in the README.

Benefits

The value gets increased visibility to users, so they know it exists.

Possible drawbacks

More docs to maintain.

Applicable issues

• fixes Feature: Document nextcloud.postgreSqlInitContainer value #645

Additional information

Manually maintaining such a large table of values seems very tedious and error prone. I would recommend looking into a tool to automate it, for example Bitnami's README generator.

Checklist

• I have read the CONTRIBUTING.md doc.
• DCO has been signed off on the commit.
• Chart version bumped in Chart.yaml according to semver.
• (optional) Parameters are documented in the README.md

[jessebot]

Manually maintaining such a large table of values seems very tedious and error prone. I would recommend looking into a tool to automate it, for example Bitnami's README generator.

This is being chatted about and worked on in #547 and #633.

[jessebot]

Thank you for the quick turn around PR :)