Clean up Go tmp directories

[Nishnha]

Go_modules creates a few temporary directories as part of the FileUpdater process. Unfortunately, we do not clean up these temporary directories up after using them, which can lead to the issue of running out of disk space. This branch was a failed attempt at cleaning up the temporary directories.

There are two spots that we create temporary directories during a go_modules update:

• At the start of the FileUpdater step if no repo_contents_path is provided

  dependabot-core/go_modules/lib/dependabot/go_modules/file_updater.rb

  Line 66 in 35032ea

  @repo_contents_path = Dir.mktmpdir

• In the go_module_updater during the update_files step (in_repo_path is in SharedHelpers and yields a temporary directory)

  dependabot-core/go_modules/lib/dependabot/go_modules/file_updater/go_mod_updater.rb

  Line 84 in 35032ea

  in_repo_path do

Attempting to remove the temporary directories immediately after either of these steps will cause failures further down the line because when we finish updating the Go files, the update_dependency_files function utilizes the vendor_updater in common which cds into each temporary directory

dependabot-core/go_modules/lib/dependabot/go_modules/file_updater.rb

Lines 45 to 48 in 35032ea

	vendor_updater.updated_vendor_cache_files(base_directory: directory).
	each do |file|
	updated_files << file
	end

Unfortunately, as d6fd635 indicates, attempting to remove the temporary directories (even with force=true) at the end of the update_dependency_files function still fails to actually remove the directories, indicating there may be an open handle preventing the folders from being removed.

I have not tried overriding the vendor_updater class for go_modules, but that could help in resolving when the temporary directories are no longer needed.

Another approach that's being tried to save on disk space during a go_modules updates is using a cache between all modules, instead of using in_repo_path and redownloading modules multiple times.