Remove redundant modifiers to address the warnings

TestFoundation/TestNSAttributedString.swift

@@ -296,19 +296,19 @@ class TestNSAttributedString : XCTestCase {
 
 fileprivate extension TestNSAttributedString {
 
-    fileprivate func describe(range: NSRange) -> String {
+    func describe(range: NSRange) -> String {
         return "(\(range.location),\(range.length))"
     }
 
-    fileprivate func describe(attr: Any?) -> String {
+    func describe(attr: Any?) -> String {
         if let attr = attr {
             return "\(attr)" + "|"
         } else {
             return "nil" + "|"
         }
     }
 
-    fileprivate func describe(attrs: [NSAttributedStringKey : Any]) -> String {
+    func describe(attrs: [NSAttributedStringKey : Any]) -> String {
         if attrs.count > 0 {
             let mapped: [String] = attrs.map({ "\($0.rawValue):\($1)" })
             let sorted: [String] = mapped.sorted(by: { $0 < $1 })

TestFoundation/TestOperationQueue.swift

@@ -203,7 +203,7 @@ class AsyncOperation: Operation {
     private var _executing = false
     private var _finished = false
 
-    override internal(set) var isExecuting: Bool {
+    override var isExecuting: Bool {
         get {
             lock.lock()
             let wasExecuting = _executing
@@ -221,7 +221,7 @@ class AsyncOperation: Operation {
         }
     }
 
-    override internal(set) var isFinished: Bool {
+    override var isFinished: Bool {
         get {
             lock.lock()
             let wasFinished = _finished

TestFoundation/TestXMLDocument.swift

@@ -547,7 +547,7 @@ class TestXMLDocument : LoopbackServerTest {
 }
 
 fileprivate extension XMLNode {
-    fileprivate func findFirstChild(named name: String) -> XMLNode? {
+    func findFirstChild(named name: String) -> XMLNode? {
         guard let children = self.children else {
             return nil
         }