fix: go mod tidy with "gorm.io/gorm latest" in go.mod file

[zyyw]

Close: #1625

the code change of this PR is done automatically by running "go mod tidy" after change github.com/jinzhu/gorm v0.0.0-20170222002820-5409931a1bb8 to gorm.io/gorm latest in the go.mod file

Verification:

1. Install harbor with notary successfully
2. the Git commit in both /var/log/harbor/notary-server.log and /var/log/harbor/notary-signer.log is 8ce2bf10.
3. export DOCKER_CONTENT_TRUST=1 && export DOCKER_CONTENT_TRUST_SERVER=https://harbor_ip:4443
4. docker push 10.92.122.104/library/nginx:1.13.12
   and having output like this:

The push refers to repository [10.92.122.104/library/nginx]
7ab428981537: Layer already exists
82b81d779f83: Layer already exists
d626a8ad97a1: Layer already exists
1.13.12: digest: sha256:e4f0474a75c510f40b37b6b7dc2516241ffa8bde5a442bde3d372c9519c84d90 size: 948
Signing and pushing trust metadata
You are about to create a new root signing key passphrase. This passphrase
will be used to protect the most sensitive key in your signing system. Please
choose a long, complex passphrase and be careful to keep the password and the
key file itself secure and backed up. It is highly recommended that you use a
password manager to generate the passphrase and keep it safe. There will be no
way to recover this key. You can find the key in your config directory.
Enter passphrase for new root key with ID 583471c:
Repeat passphrase for new root key with ID 583471c:
Enter passphrase for new repository key with ID cc1ed27:
Repeat passphrase for new repository key with ID cc1ed27:
Finished initializing "10.92.122.104/library/nginx"
Successfully signed 10.92.122.104/library/nginx:1.13.12

Conclusion:
Build notary images based on the change of this PR, notary-server and notary-signer are working fine in harbor and can sign images.

[jonnystoten]

This was done in #1639 so this can be closed.

[tomaszkrzyzanowski]

@zyyw I'm afraid you made a mistake while updating the library, because in go.mod there is still this:
github.com/jinzhu/gorm v1.9.16
and this version is pretty old:
https://github.com/jinzhu/gorm/tree/v1.9.16 (last commit 2020)