scripts/support/cve.py: avoid a complete clone of the CVE git repository

Just a simple clone and pull with --depth 1 should be enough to parse
the CVE data and generate the pkg-stats report.

From a full clone and a depth-1 clone, and the size delta is 2.9GiB
vs. 2.2GiB.

The download size does change: from 983.55MiB down to 270.78MiB.

It's a net time win too: 2m17s vs 1min7s (on a 100Mbps link).

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

support/scripts/cve.py

@@ -72,7 +72,7 @@ class CVE:
         print(f"Updating from {NVD_BASE_URL}")
         if os.path.exists(nvd_git_dir):
             subprocess.check_call(
-                ["git", "pull"],
+                ["git", "pull", "--depth", "1"],
                 cwd=nvd_git_dir,
                 stdout=subprocess.DEVNULL,
                 stderr=subprocess.DEVNULL,
@@ -82,7 +82,7 @@ class CVE:
             # happily clones into an empty directory.
             os.makedirs(nvd_git_dir)
             subprocess.check_call(
-                ["git", "clone", NVD_BASE_URL, nvd_git_dir],
+                ["git", "clone", "--depth", "1", NVD_BASE_URL, nvd_git_dir],
                 stdout=subprocess.DEVNULL,
                 stderr=subprocess.DEVNULL,
             )