Add missing `OP_POWER` operator to `Variant`

(cherry picked from commit f037a697eb)

binding_generator.py

@@ -2433,6 +2433,7 @@ def get_operator_id_name(op):
         "unary-": "negate",
         "unary+": "positive",
         "%": "module",
+        "**": "power",
         "<<": "shift_left",
         ">>": "shift_right",
         "&": "bit_and",

include/godot_cpp/variant/variant.hpp

@@ -122,6 +122,7 @@ public:
 		OP_NEGATE,
 		OP_POSITIVE,
 		OP_MODULE,
+		OP_POWER,
 		// bitwise
 		OP_SHIFT_LEFT,
 		OP_SHIFT_RIGHT,