Update operation.py docs

[J-C-Q]

Summary

One "add" too much :)

Details and comments

I removed it.

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[coveralls]

Pull Request Test Coverage Report for Build 9320628178

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 8 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.009%) to 89.572%

---

Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/lex.rs	2	92.62%
crates/qasm2/src/parse.rs	6	96.69%

Totals
Change from base Build 9318953704:	-0.009%
Covered Lines:	62345
Relevant Lines:	69603

---

💛 - Coveralls