Remove weird comment in parse_dates.py
Was added back in #12915...not sure why I did that. 😕 
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/22418?src=pr&el=h1) Report
> Merging [#22418](https://codecov.io/gh/pandas-dev/pandas/pull/22418?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/8bb2cc19ca3aa347d086b4fb5704ca9a3723172f?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/22418/graphs/tree.svg?width=650&src=pr&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/22418?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #22418   +/-   ##
=======================================
  Coverage   92.05%   92.05%           
=======================================
  Files         169      169           
  Lines       50713    50713           
=======================================
  Hits        46683    46683           
  Misses       4030     4030
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.46% <ø> (ø)` | :arrow_up: |
| #single | `42.25% <ø> (ø)` | :arrow_up: |


------

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