fix: remove mutation bugs

[ericfortmeyer]

Removing and updating was broken.

[coveralls]

Pull Request Test Coverage Report for Build 4425213414

• 13 of 15 (86.67%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.9%) to 98.077%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/CsvFileStorage.php	13	15	86.67%

Totals
Change from base Build 4400708998:	-1.9%
Covered Lines:	102
Relevant Lines:	104

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 4425213414

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

• 13 of 15 (86.67%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.9%) to 98.077%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/CsvFileStorage.php	13	15	86.67%

Totals
Change from base Build 4400708998:	-1.9%
Covered Lines:	102
Relevant Lines:	104

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 4425213414

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

• 13 of 15 (86.67%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.9%) to 98.077%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/CsvFileStorage.php	13	15	86.67%

Totals
Change from base Build 4400708998:	-1.9%
Covered Lines:	102
Relevant Lines:	104

---

💛 - Coveralls