TST: xfail non-writeable pytables tests with numpy 1.16x
closes #25511

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=h1) Report
> Merging [#25517](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/ae4db8665484a0082949cef0acf16559c07c922f?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/25517/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #25517      +/-   ##
==========================================
- Coverage   91.75%   91.74%   -0.01%     
==========================================
  Files         173      173              
  Lines       52955    52956       +1     
==========================================
- Hits        48589    48587       -2     
- Misses       4366     4369       +3
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.32% <100%> (ø)` | :arrow_up: |
| #single | `41.72% <100%> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/compat/numpy/\_\_init\_\_.py](https://codecov.io/gh/pandas-dev/pandas/pull/25517/diff?src=pr&el=tree#diff-cGFuZGFzL2NvbXBhdC9udW1weS9fX2luaXRfXy5weQ==) | `93.33% <100%> (+0.22%)` | :arrow_up: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/25517/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `87.57% <0%> (-0.1%)` | :arrow_down: |
| [pandas/io/pytables.py](https://codecov.io/gh/pandas-dev/pandas/pull/25517/diff?src=pr&el=tree#diff-cGFuZGFzL2lvL3B5dGFibGVzLnB5) | `90.11% <0%> (-0.09%)` | :arrow_down: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=continue).
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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=footer). Last update [ae4db86...1135cd0](https://codecov.io/gh/pandas-dev/pandas/pull/25517?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Owee, I'm MrMeeseeks, Look at me.

There seem to be a conflict, please backport manually. Here are approximate instructions:

1. Checkout backport branch and update it.

```
$ git checkout 0.24.x
$ git pull
```

2. Cherry pick the first parent branch of the this PR on top of the older branch:
```
$ git cherry-pick -m1 3e3c9019a11fbdf9e61fc36ca216fd128c25ae04
```

3. You will likely have some merge/cherry-pick conflict here, fix them and commit:

```
$ git commit -am 'Backport PR #25517: TST: xfail non-writeable pytables tests with numpy 1.16x'
```

4. Push to a named branch :

```
git push YOURFORK 0.24.x:auto-backport-of-pr-25517-on-0.24.x
```

5. Create a PR against branch 0.24.x, I would have named this PR:

> "Backport PR #25517 on branch 0.24.x"

And apply the correct labels and milestones.

Congratulation you did some good work ! Hopefully your backport PR will be tested by the continuous integration and merged soon!

If these instruction are inaccurate, feel free to [suggest an improvement](https://github.com/MeeseeksBox/MeeseeksDev).
                