fix(config): verify testMatchPatterns contain RegExp instance or string

[ahnpnl]

Summary

Jest config which is passed to transformer doesn’t always contain the correct value of testRegex, see jestjs/jest#9778. Since we rely on this, we should add a filter to make sure we get out the patterns which are RegExp instance or type string.

Also we add a fallback to default testMatch value, see https://jestjs.io/docs/en/configuration#testmatch-arraystring in case no patterns valid by the check above.

Fix #1552

Test plan

• Added unit tests.
• Green CI

Does this PR introduce a breaking change?

• Yes
• No

Other information

N.A.

[ahnpnl]

@kulshekhar this can be released as a bug fix version if we need so I target merge to master.

[coveralls]

Pull Request Test Coverage Report for Build 4543

• 7 of 7 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.04%) to 92.884%

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Totals
Change from base Build 4538:	0.04%
Covered Lines:	1120
Relevant Lines:	1155

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💛 - Coveralls