TST: Parse dates with empty space (#6428)
 - [x] closes #6428
 - [x] tests added / passed
 - [x] passes ``git diff upstream/master | flake8 --diff``

Parsing a date with an empty space no longer returns today's date on master 0.19.1. Not sure when this was fixed, but it doesn't seem like it occurred recently.

## [Current coverage](https://codecov.io/gh/pandas-dev/pandas/pull/14862?src=pr) is 85.30% (diff: 100%)
> Merging [#14862](https://codecov.io/gh/pandas-dev/pandas/pull/14862?src=pr) into [master](https://codecov.io/gh/pandas-dev/pandas/branch/master?src=pr) will not change coverage

```diff
@@             master     #14862   diff @@
==========================================
  Files           144        144          
  Lines         50957      50957          
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
  Hits          43469      43469          
  Misses         7488       7488          
  Partials          0          0          
```

> Powered by [Codecov](https://codecov.io?src=pr). Last update [86233e1...36bc9b7](https://codecov.io/gh/pandas-dev/pandas/compare/86233e15193c3bcd0f646915891ca6c7892335d9...36bc9b75a4975b67f879d73536b5cb9a27811b75?src=pr) @mroeschke Thanks!