DOC: cleanup of v0.23.0.txt
Cleanup of some errors in ``v.0.23.0.txt``
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21007?src=pr&el=h1) Report
> Merging [#21007](https://codecov.io/gh/pandas-dev/pandas/pull/21007?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/52effcb6848c05226bfdc103e28beb01d972c63f?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/21007/graphs/tree.svg?token=eZ4WkYLtcO&width=650&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/21007?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #21007   +/-   ##
=======================================
  Coverage   91.82%   91.82%           
=======================================
  Files         153      153           
  Lines       49491    49491           
=======================================
  Hits        45446    45446           
  Misses       4045     4045
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.22% <ø> (ø)` | :arrow_up: |
| #single | `41.85% <ø> (ø)` | :arrow_up: |


------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/21007?src=pr&el=footer). Last update [52effcb...efbb65e](https://codecov.io/gh/pandas-dev/pandas/pull/21007?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Thanks!