feat(integ-runner): add --role-arn CLI option to override CFN role

[Abogical]

Add a --role-arn CLI flag to integ-runner that overrides the CloudFormation execution and deploy role for deploy, destroy, and watch operations.

The CLI flag takes precedence over any roleArn set in the integ manifest via cdkCommandOptions.destroy.args.roleArn.

This is helpful in cases where we want to use an Admin role different from the CDK bootstrap role. This is helpful in cases where we clean up accounts and the bootstrap role itself is deleted, leading to CFN stacks that cannot be deleted without that role by default.

Checklist

• This change contains a major version upgrade for a dependency and I confirm all breaking changes are addressed
  • Release notes for the new version:

---

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.18%. Comparing base (bd58d4d) to head (c90def2).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1541      +/-   ##
==========================================
+ Coverage   88.16%   88.18%   +0.01%     
==========================================
  Files          76       76              
  Lines       10839    10839              
  Branches     1494     1493       -1     
==========================================
+ Hits         9556     9558       +2     
+ Misses       1255     1253       -2     
  Partials       28       28              

Flag	Coverage Δ
suite.unit	88.18% <ø> (+0.01%)	⬆️

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