Description

This PR enhances About plugin by adding 2 new cfg props, it includes:

• 'showAboutContent' to show/hide the content section in About plugin
• 'showVersionInfo' to show/hide the version info section.
• They are true value by default.

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://github.com/geosolutions-it/MapStore2/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x", remove the others)

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

Issue

What is the current behavior?
#10660

What is the new behavior?
If cfg of About plugin, 'showAboutContent' and 'showVersionInfo' can be added with bool values.

Breaking change

Does this PR introduce a breaking change? (check one with "x", remove the other)

• Yes, and I documented them in migration notes
• No

Other useful information

Sample of About plugin in localConfig to hide version info section:

{
   "name": "About",
       "cfg": {
           "githubUrl": "https://github.com/geosolutions-it/MapStore2/tree/",
                "showVersionInfo": false
       }
},

Sample of About plugin in localConfig to hide about content section:

{
   "name": "About",
       "cfg": {
           "githubUrl": "https://github.com/geosolutions-it/MapStore2/tree/",
          "showAboutContent": false
    }
},