Feature/minimum python version 3.9

As stated here: !4 (comment 2633787) Python version 3.7 and soon 3.8 will reach their end-of-life. This MR removes support for them.

scripts/build_hook.py

@@ -25,9 +25,7 @@ class CustomBuildHook(BuildHookInterface):
             from subprocess import check_output
 
             branch = (
-                check_output([installed_git, "rev-parse", "--abbrev-ref", "HEAD"], cwd=src_dir)  # noqa: S603
-                .decode("utf-8")
-                .strip()
+                check_output([installed_git, "rev-parse", "--abbrev-ref", "HEAD"], cwd=src_dir).decode("utf-8").strip()
             )
 
             if branch not in ["master", "develop"]: