BUG: DataFrame.corr assume 1s are always on the diagonal line
### 

- [X] I have checked that this issue has not already been reported.

- [X] I have confirmed this bug exists on the [latest version](https://pandas.pydata.org/docs/whatsnew/index.html) of pandas.

- [ ] I have confirmed this bug exists on the master branch of pandas.


### Reproducible Example

```python
import pandas as pd
import numpy as np
from scipy.spatial import distance
df = pd.DataFrame(np.ones([5,3])).corr(distance.jaccard)
print(df)

	0	1	2
0	1.0	0.0	0.0
1	0.0	1.0	0.0
2	0.0	0.0	1.0
```


### Issue Description

pd.DataFrame.corr assume diagnoal line should always be filled with one (one vector with itself). However, for many distance measures, 0 is the result when comparing two identical vectors. I think, we should allow users to specify whether to use 1 for default value on the diagnoal line, or let the underlying custom function to decide

### Expected Behavior

[[0. 0. 0.]
 [0. 0. 0.]
 [0. 0. 0.]]

### Installed Versions

<details>
INSTALLED VERSIONS
------------------
commit           : 5f648bf1706dd75a9ca0d29f26eadfbb595fe52b
python           : 3.7.6.final.0
python-bits      : 64
OS               : Windows
OS-release       : 10
Version          : 10.0.19041
machine          : AMD64
processor        : Intel64 Family 6 Model 142 Stepping 9, GenuineIntel
byteorder        : little
LC_ALL           : None
LANG             : None
LOCALE           : None.None

pandas           : 1.3.2
numpy            : 1.20.3
pytz             : 2021.1
dateutil         : 2.8.2
pip              : 21.0.1
setuptools       : 52.0.0.post20210125
Cython           : 0.29.24
pytest           : 6.2.4
hypothesis       : None
sphinx           : 4.0.2
blosc            : None
feather          : None
xlsxwriter       : 3.0.1
lxml.etree       : 4.6.3
html5lib         : 1.1
pymysql          : 0.9.3
psycopg2         : None
jinja2           : 3.0.1
IPython          : 7.26.0
pandas_datareader: 0.9.0
bs4              : 4.9.3
bottleneck       : 1.3.2
fsspec           : 2021.07.0
fastparquet      : None
gcsfs            : None
matplotlib       : 3.4.2
numexpr          : 2.7.3
odfpy            : None
openpyxl         : 3.0.7
pandas_gbq       : None
pyarrow          : None
pyxlsb           : None
s3fs             : None
scipy            : 1.6.2
sqlalchemy       : 1.4.22
tables           : 3.6.1
tabulate         : None
xarray           : None
xlrd             : 2.0.1
xlwt             : 1.3.0
numba            : 0.53.1


</details>
