[DURACOM-301] fix facets search bar appearing if last page was full

[AndreaBarbasso]

References

• Fixes Search bar in facets does not disappear if the number of facet values is a multiple of the pagination's page size #3611

Description

Removed the isAvailableForShowSearchText property in favor of using isLastPage$ only. Used the latter as a condition in order to show or hide the search bar.

Instructions for Reviewers

List of changes in this PR:

• Removed the isAvailableForShowText and replaced its use with a check for (isLastPage$ | async) === false;
• Added a test.

To reproduce the bug and its fix, as said in the linked issue:

1. Go to any search page and do a search that retrieves, for a single facet, a number of values multiple of 5;
2. Continue clicking on the "show more" button until it disappears. Now the search bar disappears.

Checklist

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