Swift: Rename predicate to avoid confusion.

Author: geoffw0

swift/ql/src/queries/Summary/FlowSources.ql

@@ -12,11 +12,11 @@
 import swift
 import codeql.swift.dataflow.FlowSources
 
-string sourceType(FlowSource s) {
+string sourceClass(FlowSource s) {
   s instanceof LocalFlowSource and result = "LocalFlowSource"
   or
   s instanceof RemoteFlowSource and result = "RemoteFlowSource"
 }
 
 from FlowSource s
-select s, sourceType(s) + ": " + s.getSourceType()
+select s, sourceClass(s) + ": " + s.getSourceType()