feat(typescript-angular): add Angular 20 support

[jase88]

fixes #21525

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[macjohnny]

thanks! would you also want to copy over the tests from https://github.com/OpenAPITools/openapi-generator/tree/4f0cce538c421de566fb183a779fb02ce00fe44e/samples/client/petstore/typescript-angular-v16-provided-in-root/tests/default/src and register them like in

openapi-generator/CI/circle_parallel.sh

Line 93 in 4f0cce5

(cd samples/client/petstore/typescript-angular-v19-provided-in-root && mvn integration-test)

this can be done in a separate PR

[anousss007]

Minestone 7.15.0 I guess ?

[macjohnny]

yeah simply the next release ;)