Bump to 7.1.1

[srawlins]

This is a bugfix release, with three fixes.

[github-actions[bot]]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:markdown	7.1.1	ready to publish	v7.1.1

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[coveralls]

Pull Request Test Coverage Report for Build 5534037383

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 96.365%

---

Totals
Change from base Build 5428567309:	0.0%
Covered Lines:	1511
Relevant Lines:	1568

---

💛 - Coveralls