Do update check only if git target or gist output (#401)

This modifies the run of the CLI to only check for new PyPI updates to
the package if a given target is a GitHub address or the output is
designated to Gist. Both of these are remote, and so the cost to check
an update (also remote) only runs in the same case.

Signed-off-by: Eric Brown <eric.brown@securesauce.dev>

precli/cli/main.py

@@ -24,6 +24,9 @@
 from precli.renderers.plain import Plain
 
 
+GITHUB_URL = "https://github.com"
+
+
 def setup_arg_parser():
     parser = argparse.ArgumentParser(
         description="precli - a static analysis security tool",
@@ -188,14 +191,14 @@ def file_to_url(owner, repo, branch, target, root, file):
     prefix = root[target_len:].lstrip("/")
     urlpath = f"{owner}/{repo}/blob/{branch}"
     rel_path = "/".join([urlpath, prefix, file])
-    return urljoin("https://github.com", rel_path)
+    return urljoin(GITHUB_URL, rel_path)
 
 
 def discover_files(targets: list[str], recursive: bool):
     artifacts = []
 
     for target in targets:
-        if target.startswith("https://github.com"):
+        if target.startswith(GITHUB_URL):
             owner, repo = get_owner_repo(target)
             if repo:
                 try:
@@ -304,7 +307,9 @@ def main():
     args = setup_arg_parser()
 
     # Check if a newer version is available
-    if args.quiet is False:
+    git_target = any(filter(lambda x: x.startswith(GITHUB_URL), args.targets))
+
+    if (git_target or args.gist) and not args.quiet:
         check_for_update()
 
     enabled = args.enable.split(",") if args.enable else []