Unified: Use CallableEx and ParameterEx in type inference implementation

Author: hvitved

unified/ql/lib/codeql/unified/internal/dataflow/CallGraph.qll

@@ -3,5 +3,5 @@ private import AllDataFlow
 private import codeql.unified.internal.typeinference.TypeInference as T
 
 DataFlowCallable viableCallable(DataFlowCall c) {
-  result.asSourceCallable() = T::resolveCallTarget(c.asExplicitCall())
+  result.asSourceCallable() = T::resolveCallTarget(c.asExplicitCall()).asCallable()
 }