feat(router-store) add selector to get title

[santoshyadavdev]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

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

What is the current behavior?

Closes #3336

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[ ] No

Other information

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[timdeschryver]

This change creates a title selector, but the result is only undefined.
We should also add title to the serializers to be able to retrieve it from the Angular route.

[santoshyadavdev]

This change creates a title selector, but the result is only undefined. We should also add title to the serializers to be able to retrieve it from the Angular route.

My bad, added it now

[brandonroberts]

@santoshyadavdev will you resolve the merge conflicts? We're ready to merge it afterwards

[santoshyadavdev]

Let me do that 😊

[santoshyadavdev]

@santoshyadavdev will you resolve the merge conflicts? We're ready to merge it afterwards

Please check now.