Fix tests on older/32 bit platforms (#60538)

(cherry picked from commit 503a17c)

Author: Catfish-Man

test/Inputs/SmallStringTestUtilities.swift

@@ -75,7 +75,8 @@ extension _SmallString {
     return nil
 #else
     guard _isObjCTaggedPointer(ns) else { return nil }
-    self.init(taggedCocoa: ns)
+    self = (ns as String)._guts.asSmall //regular tagged NSStrings are guaranteed to bridge to SmallStrings
+    assert(_StringGuts(self).isSmall)
 #endif
   }
 #endif

test/stdlib/NSSlowTaggedLocalizedString.swift

@@ -16,6 +16,11 @@ let longTaggedTests = TestSuite("NonContiguousTaggedStrings")
 var constant = "Send Message to different Team"
 
 func runEqualLongTagged() {
+  
+  if MemoryLayout<AnyObject>.size != 8 {
+    return //no tagged pointers
+  }
+  
   let native = constant.withUTF8 { String(decoding: $0, as: UTF8.self) }
   let longTagged = NSSlowTaggedLocalizedString.createTest()!
   constant.withCString {