Speed up Docker image creation in CI fuzz worfklow

[mhucka]

Is your feature request related to a use case or problem? Please explain

The CI fuzz workflow currently takes 11-12 minutes to execute. Half of it is in the creation of the fuzzer program. Part of that creation procedure is determined by the Dockerfile at https://github.com/google/oss-fuzz/blob/master/projects/cirq/Dockerfile. The efficiency of the Docker configuration and build can be improved.

Describe the solution you would prefer

Update the Dockerfile in the google/oss-fuzz repo.

[mhucka]

I opened a PR in the google/oss-fuzz repo: google/oss-fuzz#14874

Here are the steps that remain:

• get CI workflow runs approved (currently the PR is waiting for approval)
• fix any problems revealed by CI
• address review comments
• get the PR merged

[mhucka]

This should probably be an issue in the oss-fuzz repo and not here. Closing.