fix: refuse abbreviated flags in every script

argparse completed a prefix into the only flag starting with it:
slots.py --emulator read profiles from a directory named after the
emulator and reported nothing, and pipeline.py --all built every pack
variant. Every parser now refuses an abbreviation.

scripts/identity.py

@@ -133,6 +133,7 @@ def main() -> int:
     import argparse
 
     parser = argparse.ArgumentParser(
+        allow_abbrev=False,
         description="Report one content stored under identities that disagree.",
     )
     parser.add_argument("--bios-dir", default="bios")