docs: fix typo in README license filename mentions (#278)

Signed-off-by: Arthit Suriyawongkul <arthit@gmail.com>

README.md

diff --git a/README.md b/README.md
index 8b571cd..eb56fa9 100644
--- a/README.md
+++ b/README.md
@@ -54,12 +54,12 @@
 
 ## Licenses
 
-As indicated in `LICENSE-code`, tools-golang **source code files** are
+As indicated in `LICENSE.code`, tools-golang **source code files** are
 provided and may be used, at your option, under *either*:
 * Apache License, version 2.0 (**Apache-2.0**), **OR**
 * GNU General Public License, version 2.0 or later (**GPL-2.0-or-later**).
 
-As indicated in `LICENSE-docs`, tools-golang **documentation files** are
+As indicated in `LICENSE.docs`, tools-golang **documentation files** are
 provided and may be used under the Creative Commons Attribution
 4.0 International license (**CC-BY-4.0**).