bump Terraform to 1.0.0 and azurerm to 2.63

[Chambras]

Updated Docker file to easily use latest versions. Also, tflint support added.

Description

Just updated the Docker file inside the .devcontainer folder to expose tooling versions as arguments so it is easy to update to latest versions of the tooling.
I also added extra steps to install and configure tflint with azurerm support.

Issue reference

The issue this PR will close: #[issue number]

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles or validates correctly
• BASH scripts have been validated using shellcheck
• All tests pass (manual and automated)
• The documentation is updated to cover any new or changed features
• Markdown files have been linted using the recommended linter. (See .vscode/extensions.json.)
• Relevant issues are linked to this PR

[glennmusa]

Few things to consider with regard to azurerm 2.63 and the version of az CLI to pin.

One more thing, we squash and merge in this repository so the PR titles are what make up our git log. Please change the title to what change has occurred like: bump Terraform to 1.0.0 and azurerm to 2.63

[glennmusa]

Another change, the version constraint within a provider block (like we do when pulling in time) is no longer supported and would need to be removed:

provider "time" {
  version = "0.7.1"
}

to

provider "time" {
}

from https://github.com/Chambras/missionlz/blob/d9e847b0e13ea42f5a2e11209cf237c6169e4b4c/src/core/saca-hub/main.tf#L40

[Chambras]

I believe I made all suggested changes. Please do let me know if I missed something.