pip: drop support for all but current "default Python".

IMO, this recipe should be just dropped, but sadly, we still have
a few recipes using pip :-(. I consider using pip on recipes a
big NO NO, and I think we should avoid it.

Besides that...

`pip` moves too fast for us to properly keep up, and installing
pip for whatever Python version is as simple as doing:

> python3.xx -m ensurepip --altinstall
> python3.xx -m pip install --upgrade pip

(replace .xx accordingly, of course)

And then users can just update their pip whenever they like.

dev-python/pip/pip-23.2.1.recipe

@@ -3,7 +3,7 @@ DESCRIPTION="Install Python packages, replacement for easy_install"
 HOMEPAGE="https://pypi.python.org/pypi/pip"
 COPYRIGHT="2006-2023 Python Packaging Authority"
 LICENSE="Python"
-REVISION="3"
+REVISION="4"
 SOURCE_URI="https://pypi.io/packages/source/p/pip/pip-$portVersion.tar.gz"
 CHECKSUM_SHA256="fb0bd5435b3200c602b5bf61d2d43c2f13c02e29c1707567ae7fbc514eb9faf2"
 
@@ -20,15 +20,15 @@ BUILD_REQUIRES="
 	haiku_devel
 	"
 
-PYTHON_PACKAGES=(python39 python310 python311 python312)
-PYTHON_VERSIONS=(3.9 3.10 3.11 3.12)
+PYTHON_VERSIONS=(3.10)
 defaultVersion=3.10
 
-for i in "${!PYTHON_PACKAGES[@]}"; do
-	pythonPackage=${PYTHON_PACKAGES[i]}
-	pythonVersion=${PYTHON_VERSIONS[$i]}
+PYTHON_VERSIONS=(3.10)
 
-	eval "PROVIDES_${pythonPackage}=\"
+for pythonVersion in ${PYTHON_VERSIONS[@]}; do
+	pythonPackage=python${pythonVersion//.}
+
+	eval "PROVIDES_$pythonPackage=\"
 		${portName}_$pythonPackage = $portVersion
 		cmd:pip$pythonVersion
 		\""
@@ -56,9 +56,8 @@ done
 
 INSTALL()
 {
-	for i in "${!PYTHON_PACKAGES[@]}"; do
-		pythonPackage=${PYTHON_PACKAGES[i]}
-		pythonVersion=${PYTHON_VERSIONS[$i]}
+	for pythonVersion in ${PYTHON_VERSIONS[@]}; do
+		pythonPackage=python${pythonVersion//.}
 
 		python=python$pythonVersion
 		installLocation=$prefix/lib/$python/vendor-packages/
@@ -75,7 +74,7 @@ INSTALL()
 			rm $binDir/{pip,pip3}
 		fi
 
-		packageEntries  $pythonPackage \
+		packageEntries $pythonPackage \
 			$prefix/lib/python* \
 			$binDir
 	done