gradle: search for python3.11 binary for AL2023 support (#31227)

build.gradle

@@ -159,6 +159,18 @@ python {
     envPath = '.venv'
     minPythonVersion = '3.10' // should be 3.10 for local development
 
+    // Amazon Linux support.
+    // The airbyte-ci tool runs gradle tasks in AL2023-based containers.
+    // In AL2023, `python3` is necessarily v3.9, and later pythons need to be installed and named explicitly.
+    // See https://github.com/amazonlinux/amazon-linux-2023/issues/459 for details.
+    try {
+        if ("python3.11 --version".execute().waitFor() == 0) {
+            // python3.11 definitely exists at this point, use it instead of 'python3'.
+            pythonBinary "python3.11"
+        }
+    } catch (IOException _) {
+        // Swallow exception if python3.11 is not installed.
+    }
     // Pyenv support.
     try {
         def pyenvRoot = "pyenv root".execute()