Too many connections created during the startup of hacker-news example with custom read-models enabled

[FreeSlave]

I've made a branch where the number of created connections is printed - https://github.com/reimagined/resolve/tree/connection-number-dont-merge
It appears during the startup of hacker-news example there are many connections made (up to 70).
You can check it yourself by running

DEBUG_LEVEL=debug DEBUG='resolve:event-store-sqlite:*,resolve:read-model-sqlite:*' yarn dev

That happens due to the presense of custom read-models. The number of connections decreases drastically when we disable Search read-model in config.