fix(Store): memoize selector arguments

[timdeschryver]

PR Checklist

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• 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)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] 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?

Issue Number: #1389
This was also being addressed in #1194 (comment) but was forgotten.

What is the new behavior?

The arguments weren't being memoized when the result of the selector was equal to its previous result.

This fix moves the memoization of the arguments before the check if the results are equal.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

Closes #1389