[query] Add ability to set default query timeout by config

[robskillington]

What this PR does / why we need it:

Adds the ability not just to specify timeout in the header, but also adjust the default from config.

Special notes for your reviewer:

Does this PR introduce a user-facing and/or backwards incompatible change?:

NONE

Does this PR require updating code package or user-facing documentation?:

NONE

[codecov]

Codecov Report

Merging #2226 into master will decrease coverage by 0.1%.
The diff coverage is 29.4%.

@@           Coverage Diff            @@
##           master   #2226     +/-   ##
========================================
- Coverage    72.5%   72.3%   -0.2%     
========================================
  Files        1023    1023             
  Lines       89040   88939    -101     
========================================
- Hits        64566   64347    -219     
- Misses      20155   20246     +91     
- Partials     4319    4346     +27

Flag	Coverage Δ
#aggregator	62.5% <ø> (-19.7%)	⬇️
#cluster	61.7% <ø> (-23.6%)	⬇️
#collector	82.8% <ø> (ø)	⬆️
#dbnode	78.9% <ø> (-0.4%)	⬇️
#m3em	74.4% <ø> (ø)	⬆️
#m3ninx	74.4% <ø> (ø)	⬆️
#m3nsch	51.1% <ø> (ø)	⬆️
#metrics	17.5% <ø> (ø)	⬆️
#msg	74.8% <ø> (-0.2%)	⬇️
#query	68.9% <29.4%> (-0.1%)	⬇️
#x	83.2% <ø> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6c3bf71...7451f81. Read the comment docs.