chore(Dockerfile): mv pg run path to /postgresql

[hyy0322]

Using containerd as runtime, it will mount /run as tmpfs. So, change PG run path to /postgresql.

/cc @zhujian7

[caicloud-bot]

Thanks for your pull request. Before we can look at your pull request, you'll need to finish a Contributor License Agreement (CLA).

📝 Please follow instructions at https://github.com/caicloud/engineering/blob/master/guidelines/cla.md to complete the CLA.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the caicloud/tools repository. I understand the commands that are listed here.

[hyy0322]

/release-note-none

[caicloud-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
To fully approve this pull request, please assign additional approvers.
We suggest the following additional approver: supereagle

Assign the PR to them by writing /assign @supereagle in a comment when ready.

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment