Fix link to assess-scan-on-repos.sh in document

[qinheping]

Description of changes:

The link to the script of running the list of repositories in Kani document is outdated.

Resolved issues:

Resolves #ISSUE-NUMBER

Related RFC:

Optional #ISSUE-NUMBER.

Call-outs:

Testing:

• How is this change tested?

• Is this a refactor change?

Checklist

• Each commit message has a non-empty body, explaining why the change was made
• Methods or procedures are documented
• Regression or unit tests are included, or existing tests cover the modified code
• My PR is restricted to a single feature or bugfix

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