deprecate py3.6 py3.7

[JoranAngevaare]

Deprecate python 3.6 and python 3.8

Let's make the transition to py>=3.8 such that we can start using things like the walrus operator. See https://docs.python.org/3/whatsnew/3.8.html

The walrus operator

See this example, it's great

if (n := len(a)) > 10:
    print(f"List is too long ({n} elements, expected <= 10)")

[coveralls]

Pull Request Test Coverage Report for Build 1777086487

• 1 of 2 (50.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 88.897%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
strax/utils.py	1	2	50.0%

Totals
Change from base Build 1777008689:	0.0%
Covered Lines:	4604
Relevant Lines:	5179

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💛 - Coveralls

[WenzDaniel]

Looks good, thanks a lot.

[WenzDaniel]

Should mention it in Team A first though.

[JoranAngevaare]

yeah it's on the agenda