Fixes https://emqx.atlassian.net/browse/EMQX-11771
For the same reasons as we inject `emqx_bridge_*` applications as dependencies to
`emqx_bridge` when starting the node. Already configured connectors are started when
`emqx_connector` application starts, and may lead to crashes and noise in the logs. One
example is to configure a mongodb bridge and restart the node.
We need to reverse the dependency of `emqx_bridge` and `emqx_bridge_*`, because the former
loads and starts bridges during its application startup. If the individual bridge
application being loaded has not started with its dependencies, the supervision tree will
not be ready for that.