Fix Angular SSR menu issues

[YanaDePauw]

References

• Fixes Angular SSR menu issues #2503

Description

This PR fixes both the menu duplication issue when a '' child route is present as the issue with menus not rendering OnClickMenuItemModel correctly for route dependent menus.
For more information refer to the issue #2503.

Instructions for Reviewers

Add an extra menu similarly to the explanation in the issue:

1. Add a menu section for a button in the ItemPageRoutingModule to the '' route. Leave the statistics menu as is. This will result in the following route segment:

          {
            path: '',
            component: ThemedItemPageComponent,
            pathMatch: 'full',
            data: {
              menu: {
                public: [{
                  id: 'function-test',
                  active: false,
                  visible: true,
                  model: {
                    type: MenuItemType.ONCLICK,
                    text: 'Click me and verify a console log is printed.',
                    function: () => console.log('Clicking the button worked!')
                  } as OnClickMenuItemModel,
                  icon: 'hand-paper',
                  index: 3,
                }],
              },
            }
          }

2. Build the DSpace in production mode
3. Go to an item page
4. Open the console log in your browser and hard refresh the page
5. Click the entry in the navbar menu saying "Click me and verify a console log is printed."
6. Verify that no error shows up but that instead the following message is shown: "Clicking the button worked!"

Checklist

• My PR is small in size (e.g. less than 1,000 lines of code, not including comments & specs/tests), or I have provided reasons as to why that's not possible.
• My PR passes ESLint validation using yarn lint
• My PR doesn't introduce circular dependencies (verified via yarn check-circ-deps)
• My PR includes TypeDoc comments for all new (or modified) public methods and classes. It also includes TypeDoc for large or complex private methods.
• My PR passes all specs/tests and includes new/updated specs or tests based on the Code Testing Guide.
• If my PR includes new libraries/dependencies (in package.json), I've made sure their licenses align with the DSpace BSD License based on the Licensing of Contributions documentation.
• If my PR includes new features or configurations, I've provided basic technical documentation in the PR itself.
• If my PR fixes an issue ticket, I've linked them together.

[atarix83]

@YanaDePauw

thanks for this PR. Ican reproduce the bug and i verified this PR solve it.
LGTM

[dspace-bot]

Successfully created backport PR for main:

• [Port main] Fix Angular SSR menu issues #2550