fix(typescript-axios): Add missing import in case of separate models and API

[rgroothuijsen]

This amends #22642 by adding a missing import statement.

Fixes #22703

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---

Summary by cubic

Adds the missing replaceWithSerializableTypeIfNeeded import to the typescript-axios generator when models and API are generated separately. Fixes #22703 to prevent build errors in generated clients.

• Bug Fixes
  • Add the import in apiInner.mustache so generated API files reference it from common.
  • Update petstore samples to include the import.

^{Written for commit ff17b50. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 4 files

[wing328]

FYI @TiFu (2017/07) @taxpon (2017/07) @sebastianhaas (2017/07) @kenisteward (2017/07) @Vrolijkx (2017/09) @macjohnny (2018/01) @topce (2018/10) @akehir (2019/07) @petejohansonxo (2019/11) @amakhrov (2020/02) @davidgamero (2022/03) @mkusaka (2022/04) @joscha (2024/10)