Java publishing (#151)

* bindings/java: Add prefix to native methods

* bindings/java: Add javadocs and missing methods to Engine

* Setup publishing uber-JAR via GitHub workflow

* bindings/java: Update README

* bindings/java: Improve native library loading from JAR

* bindings/java: Fix usage of `working-directory`

* bindings/java: Pass required `distribution` parameter to `actions/setup-java@v4`

* bindings/java: Use Corretto distribution

This is because Microsoft doesn't provide JDK8,
see https://learn.microsoft.com/en-us/java/openjdk/download#openjdk-8.

* bindings/java: Install GCC toolchain for `aarch64-unknown-linux-gnu`

* bindings/java: Upload artifacts with different names from each step

* bindings/java: Upload built JARs to GitHub

bindings/java/tools/testbuild.py

@@ -0,0 +1,17 @@
+#!/usr/bin/env python3
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+#
+# Builds Regorus Java to use in Java tests. See `pom.xml`.
+
+from pathlib import Path
+import subprocess
+
+if __name__ == "__main__":
+    basedir = Path(__file__).parent.parent
+
+    output = basedir / "target"
+    Path(output).mkdir(exist_ok=True, parents=True)
+    cmd = ["cargo", "build", "--target-dir", str(output)]
+    print("$ " + subprocess.list2cmdline(cmd))
+    subprocess.run(cmd, cwd=basedir, check=True)