Update test containers.

Author: baagaard-usgs

azure-pipelines.yml

@@ -4,7 +4,7 @@ trigger:
   - main
 
 pool:
-  vmImage: "ubuntu-20.04"
+  vmImage: "ubuntu-22.04"
 
 variables:
   IMAGE_REGISTRY: "ghcr.io/geodynamics/pylith_installer"
@@ -48,10 +48,12 @@ stages:
               BASE_IMAGE: "testenv-ubuntu-22.04"
             ubuntu_23.04:
               BASE_IMAGE: "testenv-ubuntu-23.04"
-            fedora_37:
-              BASE_IMAGE: "testenv-fedora-37"
+            ubuntu_23.10:
+              BASE_IMAGE: "testenv-ubuntu-23.10"
             fedora_38:
               BASE_IMAGE: "testenv-fedora-38"
+            fedora_39:
+              BASE_IMAGE: "testenv-fedora-39"
             centos_7:
               BASE_IMAGE: "testenv-centos-7"
             rockylinux_8: