[typescript-fetch] add bearer token support (!3097) · Merge requests · OpenAPI Tools / openapi-generator

Created by: ken210

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Ran the shell script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh, ./bin/openapi3/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates). Windows batch files can be found in .\bin\windows\. If contributing template-only or documentation-only changes which will change sample output, be sure to build the project first.
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This PR is a follow-up of https://github.com/OpenAPITools/openapi-generator/pull/3090 Unfortunately I messed up that branch's history, so I opened another PR including the changes suggested by @macjohnny and @wing328

This PR aims to add support for Bearer authentication token to typescript-fetch generator. This PR is inspired by: https://github.com/mrvdot/openapi-generator/commit/82f409cd24c1a1ef621eb7cad46beaa316f7e955