build: add import of casnode conf

[baka-world]

Problem

discuzx/casdoor_init.go calls conf.GetConfigString() but doesn't import github.com/casbin/casnode/conf, so the discuzx package fails to build:

# github.com/casbin/casnode/discuzx
discuzx/casdoor_init.go:29:24: undefined: conf
discuzx/casdoor_init.go:30:23: undefined: conf

It is introduced in commit: 74e0fd9 . The CI go build at the repo root doesn't compile the discuzx package (nothing imports it), so the error is not caught in CI.

Fix

Add "github.com/casbin/casnode/conf" to the imports of discuzx/casdoor_init.go.

Tests

go build ./discuzx/

now succeeds with no output.

• Fixes [bug] fix undefined conf build error in discuzx package #11

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[baka-world]

I have agreed to the CLA.