use routerLink for counters section

[floriangantner]

WIP: still working on some tests, although the whole component functionality tests are currently skipped.

References

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Fixes: #19

Description

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Instructions for Reviewers

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List of changes in this PR:

• use routerLink instead of link for smoother performance when interacting with the section (no reload)
• routerLink and additional QueryParams are possible

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[floriangantner]

meanwhile superseded by similar commit c1c5a66#diff-fa2b04cc8f2b5b8a618883582c9320466bdc4c36f1f14506164744cefe370f1f