Fix companion_class_method name

Author: DarkDimius

src/dotty/tools/dotc/core/StdNames.scala

@@ -125,7 +125,7 @@ object StdNames {
     val DEFAULT_EXCEPTION_NAME: N     = "ex$"
     val INITIALIZER_PREFIX: N         = "initial$"
     val COMPANION_MODULE_METHOD: N    = "companion$module"
-    val COMPANION_CLASS_METHOD: N     = "compaion$class"
+    val COMPANION_CLASS_METHOD: N     = "companion$class"
 
     // value types (and AnyRef) are all used as terms as well
     // as (at least) arguments to the @specialize annotation.