Merge pull request #2971 from spevans/pr_urlsession_fix2

URLSession: Update maximum redirects allowed from 16 to 20 to match macOS 11

Author: spevans

Sources/FoundationNetworking/URLSession/HTTP/HTTPURLProtocol.swift

@@ -448,7 +448,7 @@ internal class _HTTPURLProtocol: _NativeProtocol {
         // Avoid a never ending redirect chain by having a hard limit on the number of redirects.
         // This value mirrors Darwin.
         redirectCount += 1
-        if redirectCount > 16 {
+        if redirectCount > 20 {
             self.internalState = .transferFailed
             let error = NSError(domain: NSURLErrorDomain, code: NSURLErrorHTTPTooManyRedirects,
                                 userInfo: [NSLocalizedDescriptionKey: "too many HTTP redirects"])

Tests/Foundation/Tests/TestURLSession.swift

@@ -829,7 +829,7 @@ class TestURLSession: LoopbackServerTest {
     }
 
     func test_httpRedirectionExceededMaxRedirects() throws {
-        let expectedMaxRedirects = 16
+        let expectedMaxRedirects = 20
         let urlString = "http://127.0.0.1:\(TestURLSession.serverPort)/redirect/99"
         let url = try XCTUnwrap(URL(string: urlString))
         let exceededCountUrlString = "http://127.0.0.1:\(TestURLSession.serverPort)/redirect/\(99 - expectedMaxRedirects)"