move TPU cleaning to GH actions

[Borda]

What does this PR do?

Move TPU cleaning to GH as here we are not restricted with nb agents

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[codecov]

Codecov Report

Merging #5991 (a5ec875) into master (27ab769) will decrease coverage by 59%.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           master   #5991     +/-   ##
========================================
- Coverage      90%     31%    -59%     
========================================
  Files         170     170             
  Lines       11784   11663    -121     
========================================
- Hits        10664    3661   -7003     
- Misses       1120    8002   +6882     

[Borda]

also lower interval to 20min

[tchaton]

LGTM !