[build] Bring naming checkstyle rules up to date with Google Style guide (#1781)

Also update Checkstyle to 8.38.

Google changed their style guide from the last time we imported it. This PR brings in those naming changes. The change they made is allowing single letter member, parameter, and local variable names. They also added a lambda naming scheme and I thought it would be good to bring that in too.

wpiutil/src/main/java/edu/wpi/first/wpiutil/RuntimeLoader.java

@@ -51,12 +51,12 @@ public final class RuntimeLoader<T> {
   private String getLoadErrorMessage(UnsatisfiedLinkError ule) {
     StringBuilder msg = new StringBuilder(512);
     msg.append(m_libraryName)
-       .append(" could not be loaded from path or an embedded resource.\n"
-               + "\tattempted to load for platform ")
-       .append(RuntimeDetector.getPlatformPath())
-       .append("\nLast Load Error: \n")
-       .append(ule.getMessage())
-       .append('\n');
+        .append(" could not be loaded from path or an embedded resource.\n"
+                + "\tattempted to load for platform ")
+        .append(RuntimeDetector.getPlatformPath())
+        .append("\nLast Load Error: \n")
+        .append(ule.getMessage())
+        .append('\n');
     if (RuntimeDetector.isWindows()) {
       msg.append("A common cause of this error is missing the C++ runtime.\n"
                  + "Download the latest at https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads\n");