Fix broken link in doc.

[NP-compete]

Issue: #614

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📚 Documentation preview 📚: https://icalendar--688.org.readthedocs.build/

[coveralls]

Pull Request Test Coverage Report for Build 9781983430

Details

• 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 97.363%

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Totals
Change from base Build 9780301065:	0.0%
Covered Lines:	3138
Relevant Lines:	3223

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💛 - Coveralls

[stevepiercy]

@NP-compete thanks for the report and contribution. Please see my comments and suggestions.

[coveralls]

Pull Request Test Coverage Report for Build 9791873487

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 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 97.363%

---

Totals
Change from base Build 9780301065:	0.0%
Covered Lines:	3138
Relevant Lines:	3223

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9791884587

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 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 97.363%

---

Totals
Change from base Build 9780301065:	0.0%
Covered Lines:	3138
Relevant Lines:	3223

---

💛 - Coveralls

[niccokunzmann]

Thanks!