Drone: Fix Windows installer upload (#27890)

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

.drone.yml

@@ -600,7 +600,7 @@ steps:
   - .\grabpl.exe windows-installer --edition oss --build-id $$env:DRONE_BUILD_NUMBER
   - $$fname = ((Get-Childitem grafana*.msi -name) -split "`n")[0]
   - gsutil cp $$fname gs://grafana-downloads/oss/master/
-  - gsutil cp $$fname.sha256 gs://grafana-downloads/oss/master/
+  - gsutil cp "$$fname.sha256" gs://grafana-downloads/oss/master/
   environment:
     GCP_KEY:
       from_secret: gcp_key

scripts/lib.star

@@ -841,7 +841,7 @@ def get_windows_steps(edition, version_mode, is_downstream=False):
             installer_commands.extend([
                 '$$fname = ((Get-Childitem grafana*.msi -name) -split "`n")[0]',
                 'gsutil cp $$fname gs://grafana-downloads/{}/{}/'.format(edition, version_mode),
-                'gsutil cp $$fname.sha256 gs://grafana-downloads/{}/{}/'.format(edition, version_mode),
+                'gsutil cp "$$fname.sha256" gs://grafana-downloads/{}/{}/'.format(edition, version_mode),
             ])
         steps.append({
             'name': 'build-windows-installer',