Fix Typos (NFC) (#5137)

wpiutil/src/test/native/cpp/json/unit-unicode.cpp

@@ -1028,7 +1028,7 @@ TEST(JsonUnicodeTest, ReadAllUnicode)
     json j;
     CHECK_NOTHROW(f >> j);
 
-    // the array has 1112064 + 1 elemnts (a terminating "null" value)
+    // the array has 1112064 + 1 elements (a terminating "null" value)
     // Note: 1112064 = 0x1FFFFF code points - 2048 invalid values between
     // 0xD800 and 0xDFFF.
     CHECK(j.size() == 1112065);

wpiutil/src/test/native/cpp/priority_mutex_test.cpp

@@ -157,7 +157,7 @@ class HighPriorityThread {
 //
 // To run the test, we need 3 threads, and then 1 thread to kick the test off.
 // The threads must all run on the same core, otherwise they wouldn't starve
-// eachother. The threads and their roles are as follows:
+// each other. The threads and their roles are as follows:
 //
 // Low priority thread:
 //   Holds a lock that the high priority thread needs, and releases it upon