Simplify logic in varmap

[basepi]

What does this pull request do?

I merged #1593 before following up on #1592 -- @kohlmanj-hs had an excellent recommendation there to simplify my logic from #1593. Thus, this PR.

[ghost]

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• Start Time: 2022-07-22T16:52:06.096+0000

• Duration: 29 min 12 sec

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Test	Results
Failed	0
Passed	4922
Skipped	3455
Total	8377

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (68/68)	💚
Files	100.0% (227/227)	💚
Classes	100.0% (227/227)	💚
Lines	89.641% (17255/19249)	👍 0.021
Conditionals	76.869% (3147/4094)	👍 0.098

[beniwohli]

LGTM!