Use verify_py38 for anaconda3-2020.07

Per the release notes the installer and base environment (which I assume
we'd be verifying here, if anything) is Python 3.8.

plugins/python-build/share/python-build/anaconda3-2020.07

@@ -1,12 +1,12 @@
 case "$(anaconda_architecture 2>/dev/null || true)" in
 "Linux-ppc64le" )
-  install_script "Anaconda3-2020.07-Linux-ppc64le" "https://repo.continuum.io/archive/Anaconda3-2020.07-Linux-ppc64le.sh#0df7c3784973ab46a9ef9848aced01311d08a71d79a18d5ed79dccdae8c8dea7" "anaconda" verify_py37
+  install_script "Anaconda3-2020.07-Linux-ppc64le" "https://repo.continuum.io/archive/Anaconda3-2020.07-Linux-ppc64le.sh#0df7c3784973ab46a9ef9848aced01311d08a71d79a18d5ed79dccdae8c8dea7" "anaconda" verify_py38
   ;;
 "Linux-x86_64" )
-  install_script "Anaconda3-2020.07-Linux-x86_64" "https://repo.continuum.io/archive/Anaconda3-2020.07-Linux-x86_64.sh#38ce717758b95b3bd0b1797cc6ccfb76f29a90c25bdfa50ee45f11e583edfdbf" "anaconda" verify_py37
+  install_script "Anaconda3-2020.07-Linux-x86_64" "https://repo.continuum.io/archive/Anaconda3-2020.07-Linux-x86_64.sh#38ce717758b95b3bd0b1797cc6ccfb76f29a90c25bdfa50ee45f11e583edfdbf" "anaconda" verify_py38
   ;;
 "MacOSX-x86_64" )
-  install_script "Anaconda3-2020.07-MacOSX-x86_64" "https://repo.continuum.io/archive/Anaconda3-2020.07-MacOSX-x86_64.sh#3980c2a57fde5de2ccfdf0d7973f95ac1a3fa63351642e6735c50fc3791ef0f1" "anaconda" verify_py37
+  install_script "Anaconda3-2020.07-MacOSX-x86_64" "https://repo.continuum.io/archive/Anaconda3-2020.07-MacOSX-x86_64.sh#3980c2a57fde5de2ccfdf0d7973f95ac1a3fa63351642e6735c50fc3791ef0f1" "anaconda" verify_py38
   ;;
 * )
   { echo