CI: ansible-core devel drops support for Python 2.7 and 3.6 (#691)

* ansible-core devel drops support for Python 2.7 and 3.6.

* Force PyYAML 5.3.1 on Alpine.

.azure-pipelines/azure-pipelines.yml

@@ -109,12 +109,8 @@ stages:
         parameters:
           testFormat: devel/linux/{0}
           targets:
-            - name: CentOS 7
-              test: centos7
-            #- name: Fedora 38
-            #  test: fedora38
-            - name: openSUSE 15
-              test: opensuse15
+            - name: Fedora 38
+              test: fedora38
             - name: Ubuntu 20.04
               test: ubuntu2004
             - name: Ubuntu 22.04
@@ -132,8 +128,10 @@ stages:
         parameters:
           testFormat: 2.16/linux/{0}
           targets:
-            - name: Fedora 38
-              test: fedora38
+            - name: CentOS 7
+              test: centos7
+            - name: openSUSE 15
+              test: opensuse15
           groups:
             - 4
             - 5
@@ -181,10 +179,6 @@ stages:
               test: debian-bookworm/3.11
             - name: ArchLinux
               test: archlinux/3.11
-            - name: CentOS Stream 8 with Python 3.6
-              test: centos-stream8/3.6
-            - name: CentOS Stream 8 with Python 3.9
-              test: centos-stream8/3.9
           groups:
             - 4
             - 5