fix: theme page displays error without management permissions.

[LIlGG]

What type of PR is this?

/kind bug
/area console
/milestone 2.6.x

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #3933

Special notes for your reviewer:

1. 创建一个拥有主题查看而没有主题管理权限的角色，并为某个用户分配这个角色。
2. 使用该用户登录 console，点击主题选项卡查看控制台是否报错。

Does this PR introduce a user-facing change?

修复没有主题管理权限时，进入主题功能页面报错的问题。

[codecov]

Codecov Report

Merging #3938 (c5a475b) into main (017bb55) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main    #3938   +/-   ##
=========================================
  Coverage     60.44%   60.44%           
  Complexity     2332     2332           
=========================================
  Files           353      353           
  Lines         12020    12020           
  Branches        872      872           
=========================================
  Hits           7265     7265           
  Misses         4325     4325           
  Partials        430      430           

[ruibaby]

/lgtm

[guqing]

/approve

[f2c-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: guqing

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• console/OWNERS [guqing]

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