Using core.summary.addList([]) should be a no-op, instead it's broken HTML

Describe the bug

To Reproduce
Steps to reproduce the behavior:

1. Use core.summary.addList([])
2. Call core.summary.stringify
3. Observe an un-closed ul tag is added to the summary contents:

Here is an example from my test suite where I happen to hit the case,

      <h1>:heavy_check_mark: statsd/statsd passed all policies</h1>
    + <ul>
      <a href="https://app.wiz.io/reports/cicd-scans#~(cicd_scan~'abc123)">View report on Wiz</a>
      ↵

Expected behavior
This should do nothing, add no content to the summary buffer.

Alternatively, adding an empty element, <ul></ul> could work.

Screenshots

Desktop (please complete the following information):

• OS: Arch
• Browser N/A
• Version node20

Smartphone (please complete the following information):
N/A

Additional context

% grep '@actions/core' yarn.lock
"@actions/core@^1.10.1", "@actions/core@^1.2.6", "@actions/core@^1.9.1":
  resolved "https://registry.yarnpkg.com/@actions/core/-/core-1.10.1.tgz#61108e7ac40acae95ee36da074fa5850ca4ced8a"
    "@actions/core" "^1.9.1"
    "@actions/core" "^1.2.6"

It's possible an un-closed ul tag is acceptable wherever you render this HTML, I tried to find a general answer and at least this says it must be closed.

Start at the core.summary.addList entry point and reproduce the issue by passing an empty array, then calling core.summary.stringify. Verify the current output and adjust the behavior so an empty list adds no content, or produces only a closed empty ul element; confirm the resulting HTML is valid.