Make the PythonHome option not stable for now

Author: steve-s

graalpython/com.oracle.graal.python.shell/src/com/oracle/graal/python/shell/GraalPythonMain.java

@@ -75,9 +75,6 @@ public static void main(String[] args) {
 
     private static final String LANGUAGE_ID = "python";
 
-    // provided by GraalVM thin launcher
-    protected static final String J_BASH_LAUNCHER_EXEC_PROPERTY_NAME = "org.graalvm.launcher.executablename";
-
     private static final String J_PYENVCFG = "pyvenv.cfg";
 
     private static long startupWallClockTime = -1;

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PythonOptions.java

@@ -92,8 +92,8 @@ private PythonOptions() {
         // no instances
     }
 
-    @Option(category = OptionCategory.USER, help = "Set the home of Python. Equivalent of GRAAL_PYTHONHOME env variable. " +
-                    "Determines default values for the CoreHome, StdLibHome, SysBasePrefix, SysPrefix.", usageSyntax = "<path>", stability = OptionStability.STABLE) //
+    @Option(category = OptionCategory.EXPERT, help = "Set the home of Python. Equivalent of GRAAL_PYTHONHOME env variable. " +
+                    "Determines default values for the CoreHome, StdLibHome, SysBasePrefix, SysPrefix.", usageSyntax = "<path>", stability = OptionStability.EXPERIMENTAL) //
     public static final OptionKey<String> PythonHome = new OptionKey<>("");
 
     @Option(category = OptionCategory.USER, help = "Set the location of sys.prefix. Overrides any environment variables or Java options.", usageSyntax = "<path>", stability = OptionStability.STABLE) //