Use right-sized runner tiers for infra workflows

.github/workflows/adhoc-command.yml

@@ -16,11 +16,20 @@ on:
         description: 'Timeout for interactive session (minutes)'
         required: false
         default: '30'
+      size:
+        description: 'Runner size'
+        required: false
+        type: choice
+        default: 'small'
+        options:
+          - small
+          - medium
+          - large
 
 jobs:
   adhoc:
     name: Run command on linux-x64
-    runs-on: [self-hosted, ce, linux, x64]
+    runs-on: ${{ inputs.size == 'large' && fromJSON('["self-hosted", "ce", "linux", "x64"]') || fromJSON(format('["self-hosted", "ce", "linux", "x64", "{0}"]', inputs.size)) }}
     # TODO in future consider github environments for this?
     if: github.actor == 'mattgodbolt' || github.actor == 'partouf'
     timeout-minutes: ${{ fromJSON(inputs.timeout_minutes) }}

.github/workflows/bespoke-build.yaml

@@ -49,9 +49,18 @@ on:
         description: Build command
         default: build.sh
         required: true
+      size:
+        description: 'Runner size'
+        required: false
+        type: choice
+        default: 'large'
+        options:
+          - small
+          - medium
+          - large
 jobs:
   bespoke-build:
-    runs-on: [ 'self-hosted', 'ce', 'linux', 'x64' ]
+    runs-on: ${{ inputs.size == 'large' && fromJSON('["self-hosted", "ce", "linux", "x64"]') || fromJSON(format('["self-hosted", "ce", "linux", "x64", "{0}"]', inputs.size)) }}
     steps:
       - name: Start from a clean directory
         uses: AutoModality/action-clean@v1.1.0

.github/workflows/consolidate.yml

@@ -16,7 +16,7 @@ on:
 jobs:
   consolidate:
     if: github.repository == 'compiler-explorer/infra'
-    runs-on: [ 'self-hosted', 'ce', 'linux', 'x64' ]
+    runs-on: [ 'self-hosted', 'ce', 'linux', 'x64', 'medium' ]
     steps:
       - name: Start from a clean directory
         uses: AutoModality/action-clean@v1.1.0

.github/workflows/install.yml

@@ -9,7 +9,7 @@ on:
         required: true
 jobs:
   install:
-    runs-on: [ 'self-hosted', 'ce', 'linux', 'x64' ]
+    runs-on: [ 'self-hosted', 'ce', 'linux', 'x64', 'small' ]
     steps:
       - name: Start from a clean directory
         uses: AutoModality/action-clean@v1.1.0