CI: Fixed pytest minversion
xref https://github.com/pandas-dev/pandas/issues/23519
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/23520?src=pr&el=h1) Report
> Merging [#23520](https://codecov.io/gh/pandas-dev/pandas/pull/23520?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/f0877eccc080cb38afa092436f09a79a65269d8c?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/23520/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/23520?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #23520   +/-   ##
=======================================
  Coverage   92.23%   92.23%           
=======================================
  Files         161      161           
  Lines       51197    51197           
=======================================
  Hits        47220    47220           
  Misses       3977     3977
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.61% <ø> (ø)` | :arrow_up: |
| #single | `42.27% <ø> (ø)` | :arrow_up: |


------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
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