Reset adaptive optimizers per batch in ASR attack

[hesseltuinhof]

Description

Fixes #910

Type of change

Please check all relevant options.

• Bug fix (non-breaking)

Testing

Please describe the tests that you ran to verify your changes. Consider listing any relevant details of your test configuration.

Test Configuration:

• Fedora 33
• Python 3.6.10
• ART 1.5.1
• PyTorch 1.5.1 with DeepSpeech 2.1

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[codecov-io]

Codecov Report

Merging #917 (7c47b82) into dev_1.5.3 (4ca921b) will decrease coverage by 24.59%.
The diff coverage is 0.00%.

@@              Coverage Diff               @@
##           dev_1.5.3     #917       +/-   ##
==============================================
- Coverage      64.93%   40.34%   -24.60%     
==============================================
  Files            176      201       +25     
  Lines          17223    17879      +656     
  Branches        3191     3277       +86     
==============================================
- Hits           11184     7213     -3971     
- Misses          4771     9857     +5086     
+ Partials        1268      809      -459     

Impacted Files	Coverage Δ
...ion/imperceptible_asr/imperceptible_asr_pytorch.py	7.26% <0.00%> (-0.09%)	⬇️
...rt/defences/detector/poison/clustering_analyzer.py	8.22% <0.00%> (-86.71%)	⬇️
...ces/detector/evasion/subsetscanning/scanningops.py	11.59% <0.00%> (-85.51%)	⬇️
art/attacks/evasion/carlini.py	8.40% <0.00%> (-80.87%)	⬇️
...ient_descent/projected_gradient_descent_pytorch.py	16.93% <0.00%> (-78.23%)	⬇️
art/metrics/verification_decisions_trees.py	13.75% <0.00%> (-73.02%)	⬇️
art/attacks/evasion/decision_tree_attack.py	22.66% <0.00%> (-69.34%)	⬇️
art/defences/detector/poison/activation_defence.py	15.71% <0.00%> (-68.90%)	⬇️
art/attacks/evasion/elastic_net.py	17.64% <0.00%> (-68.63%)	⬇️
art/defences/detector/poison/roni.py	24.05% <0.00%> (-68.36%)	⬇️
... and 105 more

[beat-buesser]

Hi @hesseltuinhof Thank you very much the updates. I have one proposal, what do you think?

[hesseltuinhof]

Thanks @beat-buesser. That was a really good spot of yours, which slipped in at the end when I made those two attributes private 😃

I updated the PR accordingly!

[beat-buesser]

Hi @hesseltuinhof Thank you very much, these are great improvements!

The tests TensorFlow 2.4.1v1 and TensorFlow+Lingvo 2.1.0v1 have not run because we changed settings in the repo when the PR was created. I have run them localyl and they are passing.