Clarify installation instructions for AWS CLI in README

[DudessaPr]

Why are these changes needed?

This PR should solve the issue: #45

I had a similar error running "make deploy-all" in Inabox directory
On the master branch I got the error which was caused by commented lines in deploy/utils.go

eigenda/inabox/deploy/utils.go

Lines 307 to 310 in 25dd873

	// TODO: When these are uncommented, the deployer sometimes fails to start anvil
	// cmd.Stdout = &out
	// cmd.Stderr = &stderr

Could not connect to docker: reached retry deadline: exit status 127: 
2024/02/25 12:27:11 reached retry deadline: exit status 127: 
exit status 1
make: *** [deploy-all] Error 1

Then on opstack-poc branch had the error something like "aws command not found". That's why I think it is important to mention the AWS CLI installation in the README file.

Checks

• I've made sure the lint is passing in this PR.
• I've made sure the tests are passing. Note that there might be a few flaky tests, in that case, please comment that they are not relevant.
• Testing Strategy
  • Unit tests
  • Integration tests
  • This PR is not tested :(