Control-Flow: Improve debug text of ReadValueInstruction

compiler/testData/cfg-variables/lexicalScopes/propertyAccessorScope.instructions

@@ -37,7 +37,7 @@ L3:
   3 <START>                                 INIT: in: {} out: {}
   4 mark({ return $a })
     magic[IMPLICIT_RECEIVER]($a) -> <v0>                            USE: in: {a=READ} out: {a=READ}
-    r($a|<v0>) -> <v1>                                              USE: in: {} out: {a=READ}
+    r($a, a|<v0>) -> <v1>                                           USE: in: {} out: {a=READ}
     ret(*|<v1>) L4
 L4:
   3 <END>

compiler/testData/cfg-variables/lexicalScopes/propertyAccessorScope.values

@@ -18,7 +18,7 @@ get() {
           }
 ---------------------
                 <v0>: A     NEW: magic[IMPLICIT_RECEIVER]($a) -> <v0>
-$a              <v1>: Int   NEW: r($a|<v0>) -> <v1>                  
+$a              <v1>: Int   NEW: r($a, a|<v0>) -> <v1>
 return $a       !<v2>: *                                             
 { return $a }   !<v2>: *    COPY                                     
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