BUG: Incorrect float format in object column
from https://github.com/pandas-dev/pandas/issues/35580#issuecomment-670245569

---

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#### Code Sample, a copy-pastable example

```
>>> pd.Series([1.0]).astype(object)
0    1
dtype: object
>>>
```

#### Problem description

[this should explain **why** the current behaviour is a problem and why the expected output is a better solution]

#### Expected Output

```
>>> pd.Series([1.0]).astype(object)
0    1.0
dtype: object
```
#### Output of ``pd.show_versions()``

<details>

[paste the output of ``pd.show_versions()`` here leaving a blank line after the details tag]

</details>
