[enhancement] Add log files in the run report

[ekouts]

Closes #2811 .

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (e527403) 86.80% compared to head (191d6d4) 86.80%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #2825   +/-   ##
========================================
  Coverage    86.80%   86.80%           
========================================
  Files           60       60           
  Lines        11395    11395           
========================================
  Hits          9891     9891           
  Misses        1504     1504           

Impacted Files	Coverage Δ
reframe/frontend/cli.py	76.62% <ø> (ø)
reframe/frontend/runreport.py	94.61% <100.00%> (ø)

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[vkarak]

I suggest making this PR against master, as it's a small enhancement rather than a new feature.

[ekouts]

Closing since #2828 is the same but against master.