Fix tag key generator output inconsistencies (#11218)

* Fix tag key generator output inconsistencies

* use NonNull instead of NotNull for generated api

---------

Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>

patches/server/Add-registry-entry-and-builders.patch

@@ -370,7 +370,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +
 +    public static <T> T asArgument(final @Nullable T value, final String field) {
 +        if (value == null) {
-+            throw new IllegalArgumentException("argument " + value + " cannot be null");
++            throw new IllegalArgumentException("argument " + field + " cannot be null");
 +        }
 +        return value;
 +    }