SAS DOC update - add documentation for sas_read(format='sas7bdat')
 - [ ] closes #12700 
 

@economy looks good thanks!

@jorisvandenbossche are you OK with merging doc fixes that aren't run before the CI finishes? yes, for small doc fixes no problem to already merge (unless it is a larger one and you want to check the doc build log) @economy thanks! # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=h1) Report
> Merging [#16420](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/d5a681bfa2de24b4a1449956c84393a413909738?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16420/graphs/tree.svg?width=650&src=pr&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #16420      +/-   ##
==========================================
- Coverage   90.42%   90.42%   -0.01%     
==========================================
  Files         161      161              
  Lines       51023    51023              
==========================================
- Hits        46137    46136       -1     
- Misses       4886     4887       +1
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.26% <ø> (-0.01%)` | :arrow_down: |
| #single | `40.17% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/indexes/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9kYXRldGltZXMucHk=) | `95.23% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16420?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/16420?src=pr&el=footer). Last update [d5a681b...099af4e](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=h1) Report
> Merging [#16420](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/d5a681bfa2de24b4a1449956c84393a413909738?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16420/graphs/tree.svg?height=150&token=eZ4WkYLtcO&src=pr&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #16420      +/-   ##
==========================================
- Coverage   90.42%   90.42%   -0.01%     
==========================================
  Files         161      161              
  Lines       51023    51023              
==========================================
- Hits        46137    46136       -1     
- Misses       4886     4887       +1
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.26% <ø> (-0.01%)` | :arrow_down: |
| #single | `40.17% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/indexes/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9kYXRldGltZXMucHk=) | `95.23% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16420?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/16420?src=pr&el=footer). Last update [d5a681b...099af4e](https://codecov.io/gh/pandas-dev/pandas/pull/16420?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
