remove nested READMEs from tech writers ownership

Author: tatomyr

.github/CODEOWNERS

@@ -1,6 +1,6 @@
 * @Redocly/dark-side
 .changeset/ @Redocly/dark-side
 .changeset/ @Redocly/technical-writers
-README.md @Redocly/dark-side
-README.md @Redocly/technical-writers
+/README.md @Redocly/dark-side
+/README.md @Redocly/technical-writers
 docs/ @Redocly/technical-writers