Remove python 3.4 from travis.

[xkdcc]

This is to fix Travis CI failure which has been seen in all PRs since 2020!
The error message in CI job as below:

Collecting PyYAML (from python-coveralls)
  Downloading https://files.pythonhosted.org/packages/64/c2/b80047c7ac2478f9501676c988a5411ed5572f35d1beff9cae07d321512c/PyYAML-5.3.1.tar.gz (269kB)
PyYAML requires Python '>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*' but the running Python is 3.4.8

The root cause of Travis CI failures is that, it will install python-coveralls latest version 2.9.3.
However, on PyPI python-coveralls 2.9.3, it has dropped Python 3.4 support.

[zongkaixuan]

Hi Brant,

I submitted a PR but seems like still failed for python 3.4 from travis. :P
https://travis-ci.org/github/aliyun/aliyun-oss-python-sdk/builds/771917170?utm_source=github_status&utm_medium=notification

"PyYAML requires Python '>=2.7, !=3.0., !=3.1., !=3.2., !=3.3., !=3.4.*' but the running Python is 3.4.8"

Thanks,

[xkdcc]

Hi Brant,

I submitted a PR but seems like still failed for python 3.4 from travis. :P
https://travis-ci.org/github/aliyun/aliyun-oss-python-sdk/builds/771917170?utm_source=github_status&utm_medium=notification

"PyYAML requires Python '>=2.7, !=3.0., !=3.1., !=3.2., !=3.3., !=3.4.*' but the running Python is 3.4.8"

Thanks,

Hi @zongkaixuan ,

When you submitted your PR, my PR (changes to remove Python 3.4) had not yet merged!
That's why you're seeing failures.
Now it should work as @huiguangjun has just merged it yesterday.