BUG: Series.replace doesn't distinguish single and double quotes
- [x] I have checked that this issue has not already been reported.
- [x] I have confirmed this bug exists on the latest version of pandas.
- [x] (optional) I have confirmed this bug exists on the master branch of pandas.

If we try to replace the single quotes in a string with double quotes or vice versa using Series.replace it doesn't work (Series.str.replace does):

```python
import pandas as pd

print(pd.__version__)
# 1.2.0.dev0+112.g0d0f53f3c
print(pd.Series([" ' ' "]).replace("'", '"'))
# 0     ' ' 
# dtype: object
print(pd.Series([" ' ' "]).str.replace("'", '"'))
# 0     " " 
# dtype: object

pd.Series([' " " ']).replace('"', "'")
# 0     " "
# dtype: object
pd.Series([' " " ']).str.replace('"', "'")
# 0     ' '
# dtype: object
```