fix: remove double suffix from default runner in image-multiarch workflow (#215)

## Summary
Fixes the double suffix issue in the `image-multiarch.yaml` reusable
workflow.

## Problem
The default `runner` input parameter had a double suffix:
```yaml
default: "ci-base-scale-set-scale-set"
```

This caused all repositories using this reusable workflow with the
default runner to get an incorrect runner name with double `-scale-set`
suffix.

## Solution
Changed the default value to:
```yaml
default: "ci-base-scale-set"
```

## Impact
This affects all repositories that use
`Typeform/.github/.github/workflows/image-multiarch.yaml@refs/tags/v1`
(or any other tag/ref) without explicitly specifying the `runner` input
parameter.

After this fix is merged and a new tag is created, repositories should
update their workflow references to use the new tag.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: pannago

.github/workflows/deep-purple-checks.yml

@@ -16,7 +16,7 @@ on:
         description: "Self-hosted GHA runner"
         type: string
         required: false
-        default: "ci-universal-scale-set-scale-set"
+        default: "ci-universal-scale-set"
 
 jobs:
   run-deep-purple-tests:

.github/workflows/frontend-deploy-workflow.yml

@@ -38,11 +38,11 @@ on:
       runner:
         description: 'Runner for build/deploy jobs'
         type: string
-        default: '["ci-universal-scale-set-scale-set"]'
+        default: '["ci-universal-scale-set"]'
       e2e-runner:
         description: 'Runner for E2E/integration tests'
         type: string
-        default: '["ci-e2e-scale-set-scale-set"]'
+        default: '["ci-e2e-scale-set"]'
 
       # Build configuration
       pre-build-command:

.github/workflows/frontend-library-pr-release-workflow.yml

@@ -13,7 +13,7 @@ on:
       runner:
         description: 'Runner to use'
         type: string
-        default: '["ci-universal-scale-set-scale-set"]'
+        default: '["ci-universal-scale-set"]'
 
       # Commands
       lint-command:

.github/workflows/frontend-pr-workflow.yml

@@ -51,11 +51,11 @@ on:
       runner:
         description: 'Runner for build/deploy jobs'
         type: string
-        default: '[ci-universal-scale-set-scale-set]'
+        default: '[ci-universal-scale-set]'
       e2e-runner:
         description: 'Runner for E2E/integration tests'
         type: string
-        default: '[ci-e2e-scale-set-scale-set]'
+        default: '[ci-e2e-scale-set]'
 
       # Build configuration
       pre-build-command:

.github/workflows/graphql-generate-persisted-operations.yml

@@ -7,7 +7,7 @@ on:
         description: "Self-hosted GHA runner"
         type: string
         required: false
-        default: "ci-universal-scale-set-scale-set"
+        default: "ci-universal-scale-set"
     secrets:
       GH_TOKEN:
         required: true

.github/workflows/image-multiarch.yaml

@@ -49,7 +49,7 @@ on:
         description: "Self-hosted GHA runner"
         type: string
         required: false
-        default: "ci-base-scale-set-scale-set"
+        default: "ci-base-scale-set"
 env:
   VERSION_PREFIX: ''
   VERSION_LATEST: latest

.github/workflows/sonarcloud-scan.yml

@@ -31,7 +31,7 @@ on:
       runner:
         description: 'Runner for SonarCloud scan'
         type: string
-        default: '[ci-universal-scale-set-scale-set]'
+        default: '[ci-universal-scale-set]'
 
       # Coverage configuration
       coverage-artifact-name: