Fixup: Drop unused val

Author: Blaisorblade

compiler/src/dotty/tools/dotc/core/TypeErrors.scala

@@ -114,7 +114,6 @@ class CyclicReference private (val denot: SymDenotation) extends TypeError {
     val unsafeFlags = cycleSym.flagsUNSAFE
     val isMethod = unsafeFlags.is(Method)
     val isVal = !isMethod && cycleSym.isTerm
-    val isImplicit = unsafeFlags.is(Implicit)
 
     /* This CyclicReference might have arisen from asking for `m`'s type while trying to infer it.
      * To try to diagnose this, walk the context chain searching for context in