fix: displaying readme of markdown format in appTemplate

[lingbohome]

What type of PR is this?

/kind bug

What this PR does / why we need it:

resolve tables in the app description readme file not rendering properly before: now:

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

Does this PR introduced a user-facing change?

fix: displaying readme of markdown format in appTemplate

Additional documentation, usage docs, etc.:

[ks-ci-bot]

Hi @lingbohome. Thanks for your PR.

I'm waiting for a kubesphere member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.

[ks-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: donniean, Leioy, lingbohome

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](https://github.com/kubesphere/console/blob/master/OWNERS)~~ [donniean] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[donniean]

/lgtm

[ks-ci-bot]

LGTM label has been added.

Git tree hash: ca0ef26df776cf4945e5d823e156a30c3a23d797