install_source: use pip -U --force-reinstall (#41401)

install_source.yml

@@ -19,9 +19,9 @@
 # Ugly hack to perform a simple 'pip install -e /some/source/dir'
 - name: "pip install {{ repo_dir }}"
   pip:
-    name: django
-    version: "{{ django_version}}"
-    extra_args: "-e {{ repo_dir }}"
+    name: "{{ repo_dir }}"
+    editable: yes
+    extra_args: "-U --force-reinstall"
     virtualenv: "{{ virtualenv }}"
 
 - name: "build {{ repo_dir }}"