pip-zipapp: ignore beta tags

Also add comments on finding sha sources on pypi

pip-zipapp.yaml

@@ -11,6 +11,15 @@ environment:
     packages:
       - busybox
 
+# See https://pip.pypa.io/en/stable/installation/#standalone-zip-application
+# Wheels for installer, setuptools, tomli, wheel, flit-core
+#
+# Hashes available from pypi (built distribution is the wheel)
+# https://pypi.org/project/installer/0.7.0/#files
+# https://pypi.org/project/setuptools/70.0.0/#files
+# https://pypi.org/project/tomli/2.0.1/#files
+# https://pypi.org/project/wheel/#files
+# https://pypi.org/project/flit-core/#files
 pipeline:
   - uses: fetch
     with:
@@ -60,6 +69,8 @@ pipeline:
       cp *.whl "$destd/$sdir/wheels/"
 
 update:
+  ignore-regex-patterns:
+    - b
   enabled: true
   github:
     identifier: pypa/pip