awscli forces upper bound on rsa version

[achave11-ucsc]

… which causes the make requirements_update target to fail if the rsa requirement is updated to a version >= 4.8.

INFO: pip is looking at multiple versions of awscli to determine which version is compatible with other requirements. This could take a while.
Cannot install -r requirements.dev.txt (line 2) and rsa==4.9 because these package versions have conflicting dependencies.

The conflict is caused by:
    The user requested rsa==4.9
    awscli 1.36.25 depends on rsa<4.8 and >=3.1.2

To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip to attempt to solve the dependency conflict

ERROR: ResolutionImpossible: for help visit https://pip.pypa.io/en/latest/topics/dependency-resolution/#dealing-with-dependency-conflicts
make: *** [Makefile:33: requirements_deps] Error 1

[hannes-ucsc]

See aws/aws-cli#8152

We should upgrade to v2 of the AWS CLI. It can't be installed with pip (not hosted on pypi) so we have to remove it and the rsa entry from requirements.dev.txt. v2 bundles a Python interpreter and can be installed via Homebrew. README should be updated accordingly. Add version check to common.mk and checklist item to upgrade issue template.

Spike to test installing v2 and making sure that our _login and envhook still work. Our _login tries to share credentials between AWS CLI and boto3/botocore. It also calls aws ecr get-login-password to log into ECR.

[hannes-ucsc]

There are currently no concrete plans to EOL v1 so we can probably wait.

See also aws/aws-cli#5294

[achave11-ucsc]

Assignee to monitor aws/aws-cli#5294.