Update codeowners

Signed-off-by: Sergen Yalçın <yalcinsergen97@gmail.com>

Author: sergenyalcin

CODEOWNERS

@@ -19,4 +19,4 @@
 # See also OWNERS.md for governance details
 
 # Fallback owners
-*			@sergenyalcin @turkenf @jastang
+*			@sergenyalcin @turkenf @jastang @ulucinar @erhancagirici

OWNERS.md

@@ -15,5 +15,7 @@ repository maintainers in their own `OWNERS.md` file.
 * Sergen Yalcin <sergen@upbound.io> ([sergenyalcin](https://github.com/sergenyalcin))
 * Fatih Turken <fatih@upbound.io> ([turkenf](https://github.com/turkenf))
 * Jason Tang <jasont@upbound.io> ([jastang](https://github.com/jastang))
+* Alper Ulucinar <alper@upbound.io> ([ulucinar](https://github.com/ulucinar))
+* Erhan Cagirici <erhan@upbound.io> ([erhancagirici](https://github.com/erhancagirici))
 
 See [CODEOWNERS](./CODEOWNERS) for automatic PR assignment.