fix pylint issues

Since pylint 2.11 it substract from the rating if you use format instead of f-strings, this fails our nightly builds for master and develop.

 pylint pyretis/bin/pyretisanalyse.py 
************* Module pyretisanalyse
pyretis/bin/pyretisanalyse.py:90:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:169:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:170:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:171:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:172:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:173:15: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:180:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:185:18: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:194:13: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:209:0: R0914: Too many local variables (17/15) (too-many-locals)
pyretis/bin/pyretisanalyse.py:278:11: W0703: Catching too general exception Exception (broad-except)
pyretis/bin/pyretisanalyse.py:252:28: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:264:28: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:271:32: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:275:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:279:17: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:282:24: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:296:14: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)
pyretis/bin/pyretisanalyse.py:301:32: C0209: Formatting a regular string which could be a f-string (consider-using-f-string)

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Your code has been rated at 8.77/10 (previous run: 8.77/10, +0.00)

This PR walks through all *MUST BE FIXED* files in master and will resolve (most) pylint issues, I will also open a similar MR for develop

Also bumped the minimal numpy version to 1.17 (still lagging behind on NEP-29) to get rid of not-a-member error on pylint for numpy.random.RandomState, by altering it to numpy.random.default_rng() instead, which was introduced in 1.17