[go-server] Modified go-server templates to allow services to receive http request's context.

[ryutah]

Modifiled go-server templates.

close #6657

Description

• Added context.Context arguments to below templates
  • api.mustache
  • controller-api.mustache
  • service.mustache
• Updated go-api-server sample by running ./bin/generate-samples.sh

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• If contributing template-only or documentation-only changes which will change sample output, build the project beforehand.
• Run the shell script ./bin/generate-samples.shto update all Petstore samples related to your fix. This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master. These must match the expectations made by your contribution. You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*. For Windows users, please run the script in Git BASH.
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[ryutah]

@antihax (2017/11) @grokify (2018/07) @kemokemo (2018/09) @bkabrda (2019/07)
Please review the pull request!

[kemokemo]

Hi @ryutah !
Thank you for your PR. This looks good to me. 😃

[wing328]

@ryutah thanks for the PR, which has been merged into master.

From what I know, this is a breaking change (without fallback) as the method signature has been changed. Please correct me if I'm wrong.

@kemokemo thanks for the prompt review.