bake: rename runner input to runs-on and defaults to empty

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

Author: crazy-max

.github/workflows/bake.yml

@@ -3,11 +3,10 @@ name: bake
 on:
   workflow_call:
     inputs:
-      runner:
+      runs-on:
         type: string
-        description: "Runner instance"
+        description: "Type of machine to run the jobs on similar to jobs.<job_id>.runs-on"
         required: false
-        default: 'auto'
       context:
         type: string
         description: "Context to build from, defaults to repository root"
@@ -135,11 +134,11 @@ env:
   DOCKER_ACTIONS_TOOLKIT_MODULE: "@docker/actions-toolkit@0.67.0"
   COSIGN_VERSION: "v3.0.2"
   LOCAL_EXPORT_DIR: "/tmp/buildx-output"
-  MATRIX_SIZE_LIMIT: 20
+  MATRIX_SIZE_LIMIT: "20"
 
 jobs:
   prepare:
-    runs-on: ${{ inputs.runner == 'auto' && 'ubuntu-latest' || inputs.runner }}
+    runs-on: ${{ inputs.runs-on || 'ubuntu-latest' }}
     outputs:
       includes: ${{ steps.set.outputs.includes }}
     steps:
@@ -169,7 +168,7 @@ jobs:
         uses: actions/github-script@v8
         env:
           INPUT_MATRIX-SIZE-LIMIT: ${{ env.MATRIX_SIZE_LIMIT }}
-          INPUT_RUNNER: ${{ inputs.runner }}
+          INPUT_RUNS-ON: ${{ inputs.runs-on || 'ubuntu-latest' }}
           INPUT_CONTEXT: ${{ inputs.context }}
           INPUT_TARGET: ${{ inputs.target }}
           INPUT_BAKE-ALLOW: ${{ inputs.bake-allow }}
@@ -185,8 +184,8 @@ jobs:
             const { Util } = require('@docker/actions-toolkit/lib/util');
 
             const inpMatrixSizeLimit = parseInt(core.getInput('matrix-size-limit'), 10);
-
-            const inpRunner = core.getInput('runner');
+            
+            const inpRunsOn = core.getInput('runs-on');
             const inpContext = core.getInput('context');
             const inpTarget = core.getInput('target');
             const inpBakeAllow = core.getInput('bake-allow');
@@ -232,18 +231,18 @@ jobs:
               } else if (platforms.length === 0) {
                 includes.push({
                   index: 0,
-                  runner: inpRunner === 'auto' ? 'ubuntu-latest' : inpRunner
+                  'runs-on': inpRunsOn
                 });
               } else {
                 platforms.forEach((platform, index) => {
-                  let runner = inpRunner;
-                  if (runner === 'auto') {
-                    runner = platform.startsWith('linux/arm') ? 'ubuntu-24.04-arm' : 'ubuntu-latest';
+                  let runsOn = inpRunsOn;
+                  if (!runsOn) {
+                    runsOn = platform.startsWith('linux/arm') ? 'ubuntu-24.04-arm' : 'ubuntu-latest';
                   }
                   includes.push({
                     index: index,
                     platform: platform,
-                    runner: runner
+                    'runs-on': runsOn
                   });
                 });
               }
@@ -252,7 +251,7 @@ jobs:
             });
 
   build:
-    runs-on: ${{ matrix.runner }}
+    runs-on: ${{ matrix.runs-on }}
     needs:
       - prepare
     permissions:
@@ -626,7 +625,7 @@ jobs:
             core.setOutput(`result_${inpIndex}`, JSON.stringify(result));
 
   post:
-    runs-on: ubuntu-latest
+    runs-on: ${{ inputs.runs-on || 'ubuntu-latest' }}
     outputs:
       cosign-version: ${{ env.COSIGN_VERSION }}
       cosign-verify-commands: ${{ steps.set.outputs.cosign-verify-commands }}