CLN: Standardize searchsorted signatures
The parameter is "value" across the board.

xref #14645.
Hello @gfyoung! Thanks for submitting the PR.

 - There are no PEP8 issues in the file [`pandas/core/arrays/categorical.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/core/arrays/categorical.py) !

 - There are no PEP8 issues in the file [`pandas/core/base.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/core/base.py) !

 - There are no PEP8 issues in the file [`pandas/core/indexes/period.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/core/indexes/period.py) !

 - There are no PEP8 issues in the file [`pandas/core/indexes/timedeltas.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/core/indexes/timedeltas.py) !

 - There are no PEP8 issues in the file [`pandas/core/series.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/core/series.py) !

 - There are no PEP8 issues in the file [`pandas/tests/arrays/categorical/test_analytics.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/tests/arrays/categorical/test_analytics.py) !

 - There are no PEP8 issues in the file [`pandas/tests/indexes/period/test_tools.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/tests/indexes/period/test_tools.py) !

 - There are no PEP8 issues in the file [`pandas/tests/series/test_analytics.py`](https://github.com/gfyoung/pandas/blob/328d8bdd2fc0fca22923dd9125461b03424283d2/pandas/tests/series/test_analytics.py) !

 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/22670?src=pr&el=h1) Report
> Merging [#22670](https://codecov.io/gh/pandas-dev/pandas/pull/22670?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/73dd6ece3b66008eb8077098c101d0e300b1e714?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/22670/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/22670?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #22670      +/-   ##
==========================================
- Coverage   92.17%   92.17%   -0.01%     
==========================================
  Files         169      169              
  Lines       50708    50702       -6     
==========================================
- Hits        46740    46734       -6     
  Misses       3968     3968
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.58% <100%> (-0.01%)` | :arrow_down: |
| #single | `42.34% <100%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/22670?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/arrays/categorical.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2NhdGVnb3JpY2FsLnB5) | `95.74% <ø> (-0.01%)` | :arrow_down: |
| [pandas/core/indexes/period.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9wZXJpb2QucHk=) | `93.48% <100%> (-0.02%)` | :arrow_down: |
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `93.72% <100%> (-0.01%)` | :arrow_down: |
| [pandas/core/base.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYmFzZS5weQ==) | `97.6% <100%> (-0.01%)` | :arrow_down: |
| [pandas/core/indexes/timedeltas.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy90aW1lZGVsdGFzLnB5) | `91.16% <100%> (-0.03%)` | :arrow_down: |
| [pandas/core/indexes/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/22670/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9kYXRldGltZXMucHk=) | `95.67% <100%> (-0.01%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/22670?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/22670?src=pr&el=footer). Last update [73dd6ec...eb9f65c](https://codecov.io/gh/pandas-dev/pandas/pull/22670?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Anyone have objections to this PR?  This is a pretty cut and dry deprecation removal. lgtm