TST: Verify that float columns stay float after pivot (#7142)
Just a test to confirm that #7142 stays fixed.  Seems to have been solved in 0.19.2.
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=h1) Report
> Merging [#16815](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/329fdaae294ae3dc45d4d7301f0f1eec2d26cb4b?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/16815/graphs/tree.svg?src=pr&token=eZ4WkYLtcO&width=650&height=150)](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #16815   +/-   ##
=======================================
  Coverage   90.94%   90.94%           
=======================================
  Files         161      161           
  Lines       49272    49272           
=======================================
  Hits        44811    44811           
  Misses       4461     4461
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.71% <ø> (ø)` | :arrow_up: |
| #single | `40.17% <ø> (ø)` | :arrow_up: |


------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16815?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/16815?src=pr&el=footer). Last update [329fdaa...0eeec92](https://codecov.io/gh/pandas-dev/pandas/pull/16815?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/16815?src=pr&el=h1) Report
> Merging [#16815](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/92e1cc829181f9a4cea47f6a81cec986e8ef2707?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/16815/graphs/tree.svg?src=pr&width=650&height=150&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #16815   +/-   ##
=======================================
  Coverage   90.94%   90.94%           
=======================================
  Files         161      161           
  Lines       49272    49272           
=======================================
  Hits        44811    44811           
  Misses       4461     4461
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.71% <ø> (ø)` | :arrow_up: |
| #single | `40.17% <ø> (ø)` | :arrow_up: |


------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16815?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/16815?src=pr&el=footer). Last update [92e1cc8...9ba6a6d](https://codecov.io/gh/pandas-dev/pandas/pull/16815?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 thanks!