samples: Blacklist some xcode environment variables

This patch unsets some Xcode environment variables in gradle
plugin and command line runner.

cmd/run_konan

@@ -74,6 +74,11 @@ java_opts=(-ea \
             "-Dkonan.home=${KONAN_HOME}" \
            -Dfile.encoding=UTF-8)
 
+# Unset some environment variables which are set by XCode and may potentially affect the tool executed.
+for VAR in `cat "${KONAN_HOME}/tools/env_blacklist"`; do
+    unset $VAR
+done
+
 KONAN_JAR="${KONAN_HOME}/konan/lib/backend.native.jar"
 KOTLIN_JAR="${KONAN_HOME}/konan/lib/kotlin-compiler.jar"
 STUB_GENERATOR_JAR="${KONAN_HOME}/konan/lib/StubGenerator.jar"