Include end row in LimitFilter

[jivanf]

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1️⃣ Why should it be added? What are the benefits of this change?

This is a fixup for #4217. That PR fixed the original issue by including the end row, but at the same time excluded the heading row, which caused #4271.

This PR modifies LimitFilter to include both the heading row and the end row, as suggested here. The tests were also updated to ensure the headings are imported correctly.

2️⃣ Does it contain multiple, unrelated changes? Please separate the PRs out.

No.

3️⃣ Does it include tests, if possible?

Yes.

4️⃣ Any drawbacks? Possible breaking changes?

Same drawbacks as #4217.

5️⃣ Mark the following tasks as done:

• Checked the codebase to ensure that your feature doesn't already exist.
• Take note of the contributing guidelines.
• Checked the pull requests to ensure that another person hasn't already submitted a fix.
• Added tests to ensure against regression.

6️⃣ Thanks for contributing! 🙌