migrate(pipx, venv) (#6004)

* migrate(pipx, venv)

suggested by @felipecrs ([here](587441621e (commitcomment-141416453))) so we don't lock users of these packages out of newer pythons (now that 3.12 is reasonably well-supported).

* link to venv/lib

* venv is picky

projects/pypa.github.io/pipx/package.yml

@@ -6,13 +6,17 @@ versions:
   github: pypa/pipx
 
 dependencies:
-  python.org: '>=3<3.12'
+  pkgx.sh: ^1
 
 build:
-  python-venv.sh "{{prefix}}"/bin/pipx
+  dependencies:
+    python.org: '>=3<3.12'
+  script:
+    - bkpyvenv stage '{{prefix}}' {{version}}
+    - ${{prefix}}/venv/bin/pip install .
+    - bkpyvenv seal '{{prefix}}' pipx
 
-test:
-  pipx run pycowsay moooo!
+test: pipx run pycowsay moooo!
 
 provides:
   - bin/pipx

projects/virtualenv.pypa.io/package.yml

@@ -7,10 +7,20 @@ versions:
   strip: /^v/
 
 dependencies:
-  python.org: '>=3.7<3.12'
+  pkgx.sh: ^1
+  libexpat.github.io: ^2
+  openssl.org: ^1.1
 
 build:
-  python-venv.sh {{prefix}}/bin/virtualenv
+  dependencies:
+    python.org: '>=3.7<3.12'
+  script:
+    - bkpyvenv stage '{{prefix}}' {{version}}
+    - ${{prefix}}/venv/bin/pip install .
+    - bkpyvenv seal '{{prefix}}' virtualenv
+    # needs this to find its libpython on linux
+    - run: cp '{{deps.python.org.prefix}}/lib/libpython'* .
+      working-directory: '{{prefix}}/lib'
 
 test:
   script: |