[Truffle] Restored alias from Kernel#inspect to Kernel#to_s.

This is done solely for bootstrapping purposes.  We override the method with a correct implementation in Ruby.

Author: nirvdrum

truffle/src/main/java/org/jruby/truffle/nodes/core/KernelNodes.java

@@ -2231,7 +2231,7 @@ public String toHexString(RubyBignum value) {
 
     }
 
-    @CoreMethod(names = "to_s")
+    @CoreMethod(names = { "to_s", "inspect" })
     public abstract static class ToSNode extends CoreMethodNode {
 
         @Child private ClassNode classNode;