TST: remove pandas-datareader xfail as 0.4.0 works
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=h1) Report
> Merging [#16374](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/88711470268cc3ee32e0b707cb61b77efbceaebd?src=pr&el=desc) will **decrease** coverage by `0.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16374/graphs/tree.svg?token=eZ4WkYLtcO&width=650&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #16374      +/-   ##
==========================================
- Coverage   90.39%   90.37%   -0.02%     
==========================================
  Files         161      161              
  Lines       50949    50951       +2     
==========================================
- Hits        46055    46049       -6     
- Misses       4894     4902       +8
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.15% <ø> (ø)` | :arrow_up: |
| #single | `40.2% <ø> (-0.11%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/io/gbq.py](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree#diff-cGFuZGFzL2lvL2dicS5weQ==) | `25% <0%> (-58.34%)` | :arrow_down: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `97.69% <0%> (-0.1%)` | :arrow_down: |
| [pandas/core/generic.py](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZ2VuZXJpYy5weQ==) | `92.13% <0%> (ø)` | :arrow_up: |
| [pandas/core/common.py](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvY29tbW9uLnB5) | `91.39% <0%> (+0.33%)` | :arrow_up: |

------

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> **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/16374?src=pr&el=footer). Last update [8871147...9e378a4](https://codecov.io/gh/pandas-dev/pandas/pull/16374?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
