GitHub Gradle build improvements (microg#2224)

* Added Gradle Wrapper validation to detect malicious or corrupted Gradlew wrappers.
Added problem matcher to automatically add GitHub annotations for build errors (especially useful for PR).

* Added a second problem matcher to detect build errors of Kotlin (apparently they are displayed differently from Java errors)

(cherry picked from commit 86b7314)

.github/matchers/gradle-build-kotlin-error-matcher.json

@@ -0,0 +1,17 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "gradle-build-kotlin-error-matcher",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^e:\\sfile:\/\/([^:]+):(\\d+):(\\d+)\\s(.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4
+        }
+      ]
+    }
+  ]
+}

.github/matchers/gradle-build-kotlin-error-matcher.json.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: none
+SPDX-License-Identifier: CC0-1.0

.github/matchers/gradle-build-matcher.json

@@ -0,0 +1,16 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "gradle-build-matcher",
+      "pattern": [
+        {
+          "regexp": "^([^:]+):(\\d+):\\s(error|Error):\\s(.+)$",
+          "file": 1,
+          "line": 2,
+          "severity": 3,
+          "message": 4
+        }
+      ]
+    }
+  ]
+}

.github/matchers/gradle-build-matcher.json.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: none
+SPDX-License-Identifier: CC0-1.0

.github/workflows/build.yml

@@ -20,7 +20,26 @@ jobs:
         with:
           distribution: "temurin"
           java-version: "17"
+      - name: "Gradle Wrapper validation"
+        uses: gradle/wrapper-validation-action@v2
       - name: "Setup Gradle"
         uses: gradle/actions/setup-gradle@v3
+      - name: "Setup matchers"
+        run: |
+          # Setting up matchers...
+
+          matchers_dir='${{ github.workspace }}/.github/matchers'
+          matcher_list()
+          {
+            echo 'gradle-build-matcher.json'
+            echo 'gradle-build-kotlin-error-matcher.json'
+          }
+
+          matcher_list | while IFS='' read -r NAME; do
+            if test -f "${matchers_dir:?}/${NAME:?}"; then
+              echo "::add-matcher::${matchers_dir:?}/${NAME:?}"
+              echo "Matcher configured: ${NAME:?}"
+            fi
+          done
       - name: "Execute Gradle build"
         run: "./gradlew --no-daemon build"