Upgrade pip in Python runtime buildpack
Upgrade pip in Python runtime buildpack

PiperOrigin-RevId: 313672859
Change-Id: I4cb05f743fc482456bb5f3cc000447f5400c7cf7

GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks,GoogleCloudPlatform/buildpacks