fix: don't panic when given a bad topology selector

[ellistarn]

Fixes #

Description
Created upstream issue: kubernetes/kubernetes#114932

For pod affinity/topology:

It appears that namespace selector is correctly validated by the API server:

Message: "Pod \"sentryfoam-5-asuppnkdet\" is invalid: spec.affinity.podAffinity.requiredDuringSchedulingIgnoredDuringExecution[0].namespaceSelector.matchLabels: Invalid value: \"{ invalid }\": a valid label must be an empty string or consist of alphanumeric characters, '-', '_' or '.', and must start and end with an alphanumeric character (e.g. 'MyValue',  or 'my_value',  or '12345', regex used for validation is '(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])?')",

But label selector is not

panic: values[0][app.kubernetes.io/name]: Invalid value: "{{ zqfmgb }}": a valid label must be an empty string or consist of alphanumeric characters, '-', '_' or '.', and must start and end with an alphanumeric character

How was this change tested?
make test

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[coveralls]

Pull Request Test Coverage Report for Build 3877899852

• 13 of 17 (76.47%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.05%) to 76.355%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/controllers/provisioning/scheduling/topology.go	5	9	55.56%

Totals
Change from base Build 3877886321:	-0.05%
Covered Lines:	5790
Relevant Lines:	7583

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💛 - Coveralls

[tzneal]

lgtm