feat: allow to request static opa binary (#24)

## Describe your changes

OPA releases statically built binaries. In the case of ARM64, it is the
only option. The setup-opa/v2 action currently supports the option.

## Reminder:

- When the PR is ready, be sure to run `npm run build` to compile into
the distribution `/dist` folder, which is the source code that the
Action uses.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Added a new input option to enable or disable the use of the static
OPA CLI binary in the GitHub Action. The option defaults to disabled.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Signed-off-by: Carlos Rodriguez-Fernandez <[email protected]>

Author: carlosrodfern

action.yml

@@ -38,6 +38,10 @@ inputs:
     description: "Version of OPA CLI to use. Default is 0.67.1."
     required: false
     default: "0.67.1"
+  opa_static:
+    description: "Whether to use the static binary. Default is false."
+    required: false
+    default: false
   indicate_source_message:
     description: Flag to comment the origins watermark (this repository) of the GitHub Action in the PR comment. Default of true.
     required: false
@@ -57,6 +61,7 @@ runs:
       uses: open-policy-agent/setup-opa@v2
       with:
         version: ${{ inputs.opa_version }}
+        static: ${{ inputs.opa_static }}
 
     - name: Run OPA Tests and Coverage
       id: opa-test-coverage