chore: make upgrade_one package=virtualenv

Author: nedbat

requirements/dev.pip

@@ -181,7 +181,7 @@ urwid==2.6.16
     #   urwid-readline
 urwid-readline==0.15.1
     # via pudb
-virtualenv==20.28.1
+virtualenv==20.29.1
     # via
     #   -r /Users/ned/coverage/trunk/requirements/pip.in
     #   tox

requirements/pip.pip

@@ -10,7 +10,7 @@ filelock==3.16.1
     # via virtualenv
 platformdirs==4.3.6
     # via virtualenv
-virtualenv==20.28.1
+virtualenv==20.29.1
     # via -r requirements/pip.in
 
 # The following packages are considered to be unsafe in a requirements file:

requirements/tox.pip

@@ -42,5 +42,5 @@ tox-gh==1.4.4
     # via -r requirements/tox.in
 typing-extensions==4.12.2
     # via tox
-virtualenv==20.28.1
+virtualenv==20.29.1
     # via tox