Enable flake8-bugbear linting and fix raised issues

Signed-off-by: Alfred Wingate <parona@protonmail.com>

src/euscan/handlers/__init__.py

@@ -13,7 +13,7 @@ from euscan import CONFIG, output
 handlers = {"package": [], "url": [], "all": {}}
 
 # autoimport all modules in this directory and append them to handlers list
-for loader, module_name, is_pkg in pkgutil.walk_packages(__path__):
+for loader, module_name, _is_pkg in pkgutil.walk_packages(__path__):
     module = loader.find_spec(module_name).loader.load_module(module_name)
     if not hasattr(module, "HANDLER_NAME"):
         continue

src/euscan/helpers.py

@@ -92,7 +92,6 @@ def version_blacklisted(cp, version):
     for bv in BLACKLIST_VERSIONS:
         if dep.match_from_list(bv, [cpv]):
             rule = bv
-            None
 
     if rule:
         euscan.output.einfo(f"{cpv} is blacklisted by rule {rule}")
@@ -223,7 +222,7 @@ def gen_versions(components, level):
 
     for i in range(n, n - level, -1):
         increment_version(components, i - 1)
-        for j in range(depth):
+        for _j in range(depth):
             versions.append(list(components))
             increment_version(components, i - 1)