Please define actions workflow permissions

## Workflow permissions improvement

There are **5 workflow files** that are currently lacking explicit permissions

### Affected Workflow Files

The following workflow files need permissions to be explicitly defined:

- [`.github/workflows/build.yml`](https://github.com/github/government.github.com/blob/main/.github/workflows/build.yml)
- [`.github/workflows/ensure-alphabetize.yml`](https://github.com/github/government.github.com/blob/main/.github/workflows/ensure-alphabetize.yml)
- [`.github/workflows/ensure-orgs.yml`](https://github.com/github/government.github.com/blob/main/.github/workflows/ensure-orgs.yml)
- [`.github/workflows/ensure-unique.yml`](https://github.com/github/government.github.com/blob/main/.github/workflows/ensure-unique.yml)
- [`.github/workflows/rubucop.yml`](https://github.com/github/government.github.com/blob/main/.github/workflows/rubucop.yml)

### Request

Ensure permissions are explicitly defined. Below are Copilot prompts/instructions if you would like Copilot's assistance with addressing this.

## GitHub Copilot Assignment Prompts and Context

**Task**: Add explicit permissions to GitHub Actions workflow files that are currently missing them.

**Scope**: Update the workflow files listed above to include appropriate `permissions:` blocks.

**Analysis Methodology**:
1. **Gather Current State**: Check if the workflow has any existing permissions defined
2. **Inventory Workflow Actions**:
- Actions performed directly by the workflow
- API calls made by the workflow
- External actions included via `uses:` statements
3. **Determine Required Permissions**: Map each action to its minimum required permissions
4. **Synthesize Minimal Permissions**: Create permissions block with only necessary permissions

**Requirements**:
1. Add a `permissions:` block to each workflow file that doesn't have one
2. Start with `contents: read` as the minimum permission
3. Add additional permissions only if the workflow actually needs them based on the actions it performs
4. Place the `permissions:` block at the job level or workflow level as appropriate
5. Ensure the syntax is correct and follows YAML formatting
6. Maintain existing content formatting, including indentation and comments

**Files to modify**: See the list of affected workflow files above.

**Acceptance criteria**:
- [ ] All listed workflow files have explicit permissions defined
- [ ] Permissions follow the principle of least privilege
- [ ] YAML syntax is valid
- [ ] Workflows still function correctly after changes

## Copilot Instructions:

Please create a pull request that adds appropriate `permissions:` blocks to each of the workflow files listed above. Analyze each workflow to determine the minimum permissions required based on the actions it performs, and add only those necessary permissions.