Revert "CI: fix conda version (#19025)"
This reverts commit c19bdc98fa3f856e2e6b3495bbab88b587801987.

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=h1) Report
> Merging [#19062](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/6552718d2a908a57b88354fe916609631793131e?src=pr&el=desc) will **increase** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/19062/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #19062      +/-   ##
==========================================
+ Coverage   91.56%   91.57%   +<.01%     
==========================================
  Files         150      150              
  Lines       48942    48942              
==========================================
+ Hits        44816    44818       +2     
+ Misses       4126     4124       -2
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.93% <ø> (ø)` | :arrow_up: |
| #single | `41.75% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/19062/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `84.95% <0%> (+0.21%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=footer). Last update [6552718...78e5cb5](https://codecov.io/gh/pandas-dev/pandas/pull/19062?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
