CLN: replace %s syntax with .format in io/formats
Progress toward issue #16130. Converted old string formatting to new string formatting in io/formats/css.py, excel.py, printing.py, style.py, and terminal.py.

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=h1) Report
> Merging [#17387](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/64c8a8d6fecacb796da8265ace870a4fcab98092?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `85.18%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/17387/graphs/tree.svg?src=pr&width=650&token=eZ4WkYLtcO&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #17387      +/-   ##
==========================================
- Coverage   91.03%   91.02%   -0.02%     
==========================================
  Files         163      163              
  Lines       49580    49580              
==========================================
- Hits        45137    45128       -9     
- Misses       4443     4452       +9
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.8% <85.18%> (ø)` | :arrow_up: |
| #single | `40.26% <33.33%> (-0.07%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/formats/style.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvc3R5bGUucHk=) | `100% <ø> (ø)` | :arrow_up: |
| [pandas/io/formats/terminal.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvdGVybWluYWwucHk=) | `16.43% <ø> (ø)` | :arrow_up: |
| [pandas/io/formats/css.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvY3NzLnB5) | `100% <100%> (ø)` | :arrow_up: |
| [pandas/io/formats/excel.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvZXhjZWwucHk=) | `96.65% <33.33%> (ø)` | :arrow_up: |
| [pandas/io/formats/printing.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2Zvcm1hdHMvcHJpbnRpbmcucHk=) | `89.38% <81.81%> (ø)` | :arrow_up: |
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.72% <0%> (-0.1%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/17387?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/17387?src=pr&el=footer). Last update [64c8a8d...705cec8](https://codecov.io/gh/pandas-dev/pandas/pull/17387?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 thanks!
