build: only rewrite stamp file after a new IB setup

No need to rewrite it every time.

Signed-off-by: Paul Spooren <[email protected]>

asu/build.py

@@ -182,6 +182,7 @@ def download_file(filename: str, dest: str = None):
     if origin_modified != local_modified:
         log.debug("New ImageBuilder upstream available")
         setup_ib()
+        stamp_file.write_text(origin_modified)
 
     if not (cache_workdir / ".config.orig").exists():
         # backup original configuration to keep default filesystems
@@ -190,8 +191,6 @@ def download_file(filename: str, dest: str = None):
             cache_workdir / ".config.orig",
         )
 
-    stamp_file.write_text(origin_modified)
-
     info_run = subprocess.run(
         ["make", "info"], text=True, capture_output=True, cwd=cache_workdir
     )