Addon Manager: Clean up backup directories

src/Mod/AddonManager/addonmanager_git.py

@@ -231,6 +231,7 @@ class GitManager:
             os.chdir(original_cwd)
             raise e
         os.chdir(original_cwd)
+        shutil.rmtree(backup_path, ignore_errors=True)
 
     def get_remote(self, local_path) -> str:
         """Get the repository that this local path is set to fetch from"""

src/Mod/AddonManager/addonmanager_workers_installation.py

@@ -147,7 +147,7 @@ class InstallWorkbenchWorker(QtCore.QThread):
         will revert to a clean clone."""
         self.status_message.emit("Updating module...")
         with self.repo.git_lock:
-            if not os.path.exists(clonedir + os.sep + ".git"):
+            if not os.path.exists(os.path.join(clonedir, ".git")):
                 self.git_manager.repair(self.repo.url, clonedir)
             try:
                 self.git_manager.update(clonedir)

src/Mod/AddonManager/developer_mode_edit_dependency.ui

@@ -51,7 +51,7 @@
         </font>
        </property>
        <property name="text">
-        <string>NOTE: If &quot;Other...&quot; is selected, the package is not in the ALLOWED_PYTHON_PACKAGES.txt file, and will not be automatically installed by the Addon Manager. Submit a PR at &lt;a href=https://github.com/FreeCAD/FreeCAD-addons&quot;&gt;https://github.com/FreeCAD/FreeCAD-addons&lt;/a&gt; to request addition of a package.</string>
+        <string>NOTE: If &quot;Other...&quot; is selected, the package is not in the ALLOWED_PYTHON_PACKAGES.txt file, and will not be automatically installed by the Addon Manager. Submit a PR at &lt;a href=&quot;https://github.com/FreeCAD/FreeCAD-addons&quot;&gt;https://github.com/FreeCAD/FreeCAD-addons&lt;/a&gt; to request addition of a package.</string>
        </property>
        <property name="wordWrap">
         <bool>true</bool>