Update versions tested in CI scripts

Drop some older/add newer Java versions for GitHub Actions.

For the Windows tests, The implementation here never honored
the PG version setting for MinGW, instead just using whatever
PG version pacman supplies, so just use PG: pacman for those
entries to avoid confusion. As MinGW is only testing one PG
version, use multiple JDK versions there.

Try several different PG versions among the MSVC entries,
without as many different JDK versions.

.github/workflows/ci-runnerpg.yml

@@ -28,7 +28,7 @@ jobs:
 #           cc: msvc
 #         - os: windows-latest
 #           cc: mingw
-        java: [9, 11, 12, 17, 18, 19]
+        java: [9, 11, 17, 19, 21]
 
     steps:
 

appveyor.yml

@@ -12,56 +12,32 @@ environment:
   APPVEYOR_RDP_PASSWORD: MrRobot@2020
   VCVARSALL: C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat
   matrix:
-#   - SYS: MINGW
-#     JDK: 9
-#     PG: 12
-#   - SYS: MINGW
-#     JDK: 10
-#     PG: 12
     - SYS: MINGW
       JDK: 11
-      PG: 12
+      PG: pacman
     - SYS: MINGW
-      JDK: 12
-      PG: 12
+      JDK: 17
+      PG: pacman
     - SYS: MINGW
-      JDK: 13
-      PG: 12
+      JDK: 19
+      PG: pacman
     - SYS: MINGW
-      JDK: 14
-      PG: 12
-    - SYS: MINGW
-      JDK: 15
-      PG: 12
+      JDK: 21
+      PG: pacman
     - SYS: MSVC
-      JDK: 15
-      PG: 12
+      JDK: 21
+      PG: 15
     - SYS: MSVC
-      JDK: 14
-      PG: 12
+      JDK: 21
+      PG: 14
     - SYS: MSVC
-      JDK: 13
-      PG: 12
+      JDK: 21
+      PG: 13
     - SYS: MSVC
-      JDK: 12
+      JDK: 21
       PG: 12
     - SYS: MSVC
       JDK: 11
-      PG: 12
-#   - SYS: MSVC
-#     JDK: 10
-#     PG: 12
-#   - SYS: MSVC
-#     JDK: 9
-#     PG: 12
-    - SYS: MSVC
-      JDK: 14
-      PG: 11
-    - SYS: MSVC
-      JDK: 14
-      PG: 10
-    - SYS: MSVC
-      JDK: 14
       PG: 9.6
 before_build:
   - ps: .appveyor/appveyor_download_java.ps1