Add mark-au to the OracleLinuxDevelopers content as CODEOWNER (#1707)

Signed-off-by: Avi Miller <[email protected]>

Author: Djelibeybi

CODEOWNERS

@@ -15,7 +15,7 @@
 /OracleHTTPServer/        @Prabhat-Kishore
 /OracleInstantClient/     @cjbj
 /OracleJava/              @aureliogrb @Djelibeybi
-/OracleLinuxDevelopers/   @Djelibeybi
+/OracleLinuxDevelopers/   @Djelibeybi @mark-au
 /OracleRestDataServices/  @gvenzl
 /OracleTuxedo/            @toddinpal
 /OracleWebCenterSites/    @prshshuk