ci: stop whitelisting appveyor branches
ci: stop whitelisting appveyor branches

This should restore appveyor builds on PRs, although getting the build
to work properly is still outstanding:

https://github.com/influxdata/influxdb/issues/10937

influxdb/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb,mark-rushakoff/influxdb,li-ang/influxdb,nooproblem/influxdb,influxdb/influxdb,influxdata/influxdb,influxdb/influxdb,influxdb/influxdb,influxdata/influxdb,li-ang/influxdb,mark-rushakoff/influxdb,nooproblem/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb,influxdb/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb