[Runtime Environment] Parse special characters in private Git URIs

[shrekris-anyscale]

Why are these changes needed?

Users can access private Git repos via runtime environments by specifying an archive link, usually containing a username and private token. For example, from the Ray documentation, the GitHub format is

https://[username]:[personal access token]@github.com/[username]/[private repository]/archive/[commit hash].zip

However, the colon (:) and at (@) symbols are not removed before parsing the URI as a directory name for the runtime environment. Since PYTHONPATHs use colons as package name separators, Python modules in this private repo can't be imported.

This change converts the colon and at symbols to underscores (_) when converting the URI into a directory name. This allows modules stored in private repos to be imported.

Related issue number

N/A

Checks

• I've signed off every commit(by using the -s flag, i.e., git commit -s) in this PR.
• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://docs.ray.io/en/master/.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • Unit tests
    • This change adds new unit tests to test_runtime_env_packaging.py.

[simon-mo]

LGTM as long as manually tested as well

[shrekris-anyscale]

I just verified manually by testing that imports from a private repo work.