DOC: Delete trailing blank lines in docstrings.
re: issue #23632

- [ ] refs #23632
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

Hello @douglatornell! Thanks for submitting the PR.

 - There are no PEP8 issues in the file [`pandas/core/series.py`](https://github.com/douglatornell/pandas/blob/c114376efdb10759f34bc0f7f62513b90ae1679e/pandas/core/series.py) !

 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/23651?src=pr&el=h1) Report
> Merging [#23651](https://codecov.io/gh/pandas-dev/pandas/pull/23651?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/a08bf3de02bb1e53fb95df24ae060b63c2a44c96?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/23651/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/23651?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #23651   +/-   ##
=======================================
  Coverage   92.24%   92.24%           
=======================================
  Files         161      161           
  Lines       51317    51317           
=======================================
  Hits        47338    47338           
  Misses       3979     3979
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.63% <ø> (ø)` | :arrow_up: |
| #single | `42.31% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/23651?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/series.py](https://codecov.io/gh/pandas-dev/pandas/pull/23651/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc2VyaWVzLnB5) | `93.7% <ø> (ø)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/23651?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/23651?src=pr&el=footer). Last update [a08bf3d...c114376](https://codecov.io/gh/pandas-dev/pandas/pull/23651?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 @gfyoung, can you take a look here (similar the one you approved before), and merge if you're happy Thanks, @douglatornell !