Allow to customize jest transformIgnorePatterns

[crubier]

Fixes #35634

Bug

• Related issues linked using fixes #number
• Integration tests added
• Errors have helpful link attached, see contributing.md

[burtek]

#35634 and this PR title say about transformIgnorePatterns, yet PR itself changes testPathIgnorePatterns?

[ijjk]

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	vercel/next.js canary	crubier/next.js patch-1	Change
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nodeModulesSize	467 MB	467 MB	-276 B

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/ failed reqs	0	0	✓
/ total time (seconds)	3.005	3.013	⚠️ +0.01
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nodeModulesSize	467 MB	467 MB	-276 B

Page Load Tests Overall increase ✓

	vercel/next.js canary	crubier/next.js patch-1	Change
/ failed reqs	0	0	✓
/ total time (seconds)	3.022	3.021	0
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framework-HASH.js gzip	42.3 kB	42.3 kB	✓
main-HASH.js gzip	28.6 kB	28.6 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
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amp-HASH.js gzip	313 B	313 B	✓
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hooks-HASH.js gzip	921 B	921 B	✓
image-HASH.js gzip	5.77 kB	5.77 kB	✓
index-HASH.js gzip	261 B	261 B	✓
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script-HASH.js gzip	394 B	394 B	✓
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85e02e95b279..7e3.css gzip	107 B	107 B	✓
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Client Build Manifests

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	vercel/next.js canary	crubier/next.js patch-1	Change
index.html gzip	532 B	532 B	✓
link.html gzip	546 B	546 B	✓
withRouter.html gzip	527 B	527 B	✓
Overall change	1.6 kB	1.6 kB	✓

Commit: 6f74264

[ijjk]

Hi, I think after further investigation in #36787 we want to leave the overriding as is for these configs and then if further overriding is needed then the returned config can be modified as shown in this comment

Thanks for the PR though!