CI: add repochecker built for Apple M1

.drone.yml

@@ -154,6 +154,16 @@ steps:
     commands:
       - go build -v -o deploy/repochecker-${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH} srs.epita.fr/fic-server/repochecker
 
+  - name: build repochecker for macOS
+    image: golang:alpine
+    commands:
+      - apk --no-cache add build-base
+      - go build -v -o deploy/repochecker-darwin-${DRONE_STAGE_ARCH} srs.epita.fr/fic-server/repochecker
+    environment:
+      CGO_ENABLED: 0
+      GOOS: darwin
+      GOARCH: arm64
+
   - name: build qa
     image: golang:alpine
     commands: