fixup! CI: Split out jobs for ARM, ESP32 and Linux

Author: jonnor

.github/workflows/build.yaml

@@ -85,7 +85,7 @@ jobs:
         name: emlearn-micropython-build-arm
         path: dist
 
-  build-linux: build-esp32
+  build-esp32:
     runs-on: ubuntu-24.04
     env:
       MPY_DIR: ./micropython