Skip package update with args

Description

Adds feature toggle --skip-package-update to install-consul.

Although not strictly a fix for all apt/yum package issues one might encounter, this suggested feature toggle is consistent with the same feature toggle with install-vault --skip-package-update.

yum/apt update is not strictly deterministic and produces different results, security vulnerabilities, or fails over time. For this reason some users may chose to produce base images that run yum update, and then continue to run installers on subsequent image builds. For this to be possible, we need the ability to install software like consul without yum/apt update, so this feature toggle allows users to do that.

Documentation

run install-consul --skip-package-update to avoid running yum/apt update with the installer. It is recommended that you have already run yum/apt update at some previous point if you choose to use this feature toggle.

TODOs

Please ensure all of these TODOs are completed before asking for a review.

[x] Ensure the branch is named correctly with the issue number. e.g: feature/new-vpc-endpoints-955 or bug/missing-count-param-434.
[ ] Update the docs.
[x] Keep the changes backward compatible where possible.
[ ] Run the pre-commit checks successfully.
[ ] Run the relevant tests successfully.
[ ] Ensure any 3rd party code adheres with our license policy or delete this line if its not applicable.

hashicorp / terraform-aws-consul