resource/gitlab_repository_file: Support auto base64 encoding for content
This change sets allows to specify not-yet base64 encoded content
and the resource will automatically base64 encode it for the API.
This will make the plan match more readable and will solve the limitations described in #956 (closed)
Initially I thought it's best to use a DiffSuppressFunc
and always store the content
as base64. However, I think it's best to store it in the same format (text vs. plan) as given in the config. This ensures that access the resource content in the config produces deterministic results.
Closes: #956 (closed)