🙏 [Help Wanted] Clean up deprecations

The Backstage CLI providers the repo list-deprecations command to list all usages of deprecated symbols. We have a lot of these in the main repo, and would like to clean them up. I think this is a good first issue for anyone that wants to get involved in the project and help out.

Steps

1. Run the following command in the project root:

yarn backstage-cli repo list-deprecations

1. You will not get a long list of deprecated usages, looking something like this:

...
packages/backend-common/src/reading/index.ts:19:10 - 'BitbucketUrlReader' is deprecated. in favor of BitbucketCloudUrlReader and BitbucketServerUrlReader
packages/backend-common/src/reading/index.ts:19:10 - 'BitbucketUrlReader' is deprecated. in favor of BitbucketCloudUrlReader and BitbucketServerUrlReader
...

1. Pick a couple of related deprecations to fix, not too many at once, but be sure to for example fix all deprecations in a single file at the same time. Generally the deprecation message should provide guidance for how to migrate. If that’s not the case, please chime in this issue so that we can help clarify an perhaps improve the deprecation message. Note that the deprecated symbols themselves should not be removed, we don’t want to change the API surface at this stage.

[Rugvip]

Big thank you to everyone that has been helping out so far! 🚀

I wanted to highlight something that’s been a somewhat common confusion, which is that we don’t want to remove the deprecated symbols themselves, including any re-exports of them and so on. There are also cases where a deprecated symbol depends on another deprecated symbol, in which case there’s no need to change the usage. The main guideline here is that we don’t want the public API of any of the packages to change at this point. When running yarn build:api-reports there should be no changes to any of the api-report.md files.

[kurtaking]

@kurtaking dang I’ve been working on a fix for cost-insights now and are nearly done, didn’t think this issue would have so much traffic at once. How far have you come?

@Znarvl please continue! I only have one commit with 6 files changed. I want to learn more about how tech-docs works so I will focus on plugins/techdocs.