fix(s3): remove `emqx_bridge_http` from runtime dependencies

Otherwise it's impossible to test `emqx_s3` in isolation.

apps/emqx_s3/src/emqx_s3.app.src

@@ -8,8 +8,7 @@
         stdlib,
         gproc,
         erlcloud,
-        ehttpc,
-        emqx_bridge_http
+        ehttpc
     ]},
     {mod, {emqx_s3_app, []}}
 ]}.