Set up parallelism for drone build

.drone.yml

@@ -28,6 +28,8 @@ steps:
       - cmake --build build-release --target all -- -j 4
       - cd build-release
       - ./ArbutilsTests -s --duration=true --force-colors=true
+    depends_on:
+      - test-debug-linux
   - name: test-release-linux_valgrind
     image: deukhoofd/linux64builder
     environment:
@@ -40,6 +42,8 @@ steps:
       - cmake --build build-release_valgrind --target all -- -j 4
       - cd build-release_valgrind
       - valgrind --tool=memcheck --gen-suppressions=all --leak-check=full --leak-resolution=med --track-origins=yes --vgdb=no --error-exitcode=1 ./ArbutilsTests
+    depends_on:
+      - test-release-linux
   - name: test-release-windows
     image: deukhoofd/windowsbuilder
     commands:
@@ -74,6 +78,6 @@ volumes:
       path: /home/docs/Arbutils
 ---
 kind: signature
-hmac: 8ee9294785e0ce2853d4cfb01ae39ddd82e1c3152b8917cc459d84cbc82e8aaf
+hmac: 8cd9f2cca97c22b86e4eefc0eb28b80fd3efa7f4aa923368d3a648648d38502b
 
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