[CI] Stop testing Mandrel for JDK 17 & 22, and graal master with 21

* Mandrel for JDK 17 and 22 are no longer supported.
* There is no indication that we will need to support builds of latest
  graal source code based on JDK 21. It has also been made clear by
  upstream GraalVM that there is no plan to keep the graal source code
  compatible with older JDKs (like 21).

.github/workflows/weekly.yml

@@ -30,33 +30,6 @@ concurrency:
 
 jobs:
   ####
-  # Test Q main and GraalVM CE JDK 21 since Mandrel 21 builds are
-  # currently not possible (#598)
-  ####
-  q-main-graal-21-latest:
-    name: "Q main G 21 latest"
-    uses: ./.github/workflows/base.yml
-    with:
-      quarkus-version: "main"
-      version: "graal/master"
-      build-type: "graal-source"
-      jdk: "21/ea"
-      build-stats-tag: "gha-linux-graal-qmain-glatest-jdk21ea"
-    secrets:
-      UPLOAD_COLLECTOR_TOKEN: ${{ secrets.UPLOAD_COLLECTOR_TOKEN }}
-  ####
-  # Test Q main and Mandrel 24.0 JDK 22 builder image
-  ####
-  q-main-mandrel-24_0:
-    name: "Q main M 24 JDK 22"
-    uses: ./.github/workflows/base.yml
-    with:
-      quarkus-version: "main"
-      build-stats-tag: "gha-linux-qmain-m24_0-builder-image"
-      builder-image: "quay.io/quarkus/ubi-quarkus-mandrel-builder-image:jdk-22"
-    secrets:
-      UPLOAD_COLLECTOR_TOKEN: ${{ secrets.UPLOAD_COLLECTOR_TOKEN }}
-  ####
   # Test Q main and Mandrel 24.1 JDK 23
   ####
   q-main-mandrel-24_1-ea:
@@ -122,15 +95,3 @@ jobs:
     secrets:
       ISSUE_BOT_TOKEN: ${{ secrets.MANDREL_BOT_TOKEN }}
       UPLOAD_COLLECTOR_TOKEN: ${{ secrets.UPLOAD_COLLECTOR_TOKEN }}
-  ####
-  # Test Quarkus 3.2 with Mandrel 23.0 JDK 17
-  ####
-  q-3_2-mandrel-23_0:
-    name: "Q 3.2 M 23.0 JDK 17"
-    uses: ./.github/workflows/base.yml
-    with:
-      quarkus-version: "3.2"
-      build-type: "mandrel-source-nolocalmvn"
-      version: "mandrel/23.0"
-      jdk: "17/ea"
-      mandrel-packaging-version: "23.0"