Update file.proto to use FileID type instead of long for file identif…

…ication (#285)

* Initial commit

* Replace instead of deprecate previous field

* change topic number to topicID (#286)

Signed-off-by: Lev Povolotsky <lev@swirldslabs.com>

* Initial commit

* Replace instead of deprecate previous field

---------

Signed-off-by: Lev Povolotsky <lev@swirldslabs.com>
Co-authored-by: Lev Povolotsky <16233475+povolev15@users.noreply.github.com>

services/state/file/file.proto

@@ -37,9 +37,9 @@ option java_multiple_files = true;
  */
 message File {
     /**
-     * The file's unique entity number in the Merkle state.
+     * The file's unique file identifier in the Merkle state.
      */
-    int64 file_number = 1;
+    FileID file_id = 1;
     /**
       * The file's consensus expiration time in seconds since the epoch.
       */