Wrong badgeUrl when rootPath is not empty in the page of repo badge settings

[andyhan]

Component

web-ui

Describe the bug

When rootPath is not empty the badge image src link is wrong in the page of repo badge settings.

System Info

{
    "source": "https://github.com/woodpecker-ci/woodpecker",
    "version": "2.1.0"
}

Additional context

Validations

• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Checked that the bug isn't fixed in the next version already [https://woodpecker-ci.org/faq#which-version-of-woodpecker-should-i-use]
• Check that this is a concrete bug. For Q&A join our Discord Chat Server or the Matrix room.

[andyhan]

Cause another problem that needs to be fixed again.