chore: do not force GOPROXY (#899)

let `setup-go` figure it out

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  - [PR](https://code.forgejo.org/forgejo/runner/pulls/899): <!--number 899 --><!--line 0 --><!--description Y2hvcmU6IGRvIG5vdCBmb3JjZSBHT1BST1hZ-->chore: do not force GOPROXY<!--description-->
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Reviewed-on: https://code.forgejo.org/forgejo/runner/pulls/899
Reviewed-by: Michael Kriese <[email protected]>
Co-authored-by: Earl Warren <[email protected]>
Co-committed-by: Earl Warren <[email protected]>

Author: earl-warren

.forgejo/workflows/test.yml

@@ -14,7 +14,6 @@ env:
   FORGEJO_RUNNER_SECRET: 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
   FORGEJO_SCRIPT: |
     /usr/bin/s6-svscan /etc/s6 & sleep 10 ; su -c "forgejo admin user create --admin --username $FORGEJO_ADMIN_USER --password $FORGEJO_ADMIN_PASSWORD --email [email protected]" git && su -c "forgejo forgejo-cli actions register --labels docker --name therunner --secret $FORGEJO_RUNNER_SECRET" git && sleep infinity
-  GOPROXY: https://goproxy.io,direct
 
 jobs:
   build-and-tests: