Misc bugfixes

[danielealbano]

This PR fixes a few minor bugs:

• Fix prometheus labels when there are none
• Expand integration tests for prometheus
• ulimit set errors are not failures so report them as warning
• Documentation fixes

[codecov[bot]]

Codecov Report

Merging #151 (b082024) into main (62ac35a) will increase coverage by 0.17%. The diff coverage is 66.66%.

@@            Coverage Diff             @@
##             main     #151      +/-   ##
==========================================
+ Coverage   80.87%   81.04%   +0.17%     
==========================================
  Files          88       88              
  Lines        5515     5514       -1     
==========================================
+ Hits         4460     4469       +9     
+ Misses       1055     1045      -10     

Impacted Files	Coverage Δ
src/program_ulimit.c	71.42% <50.00%> (+1.86%)	:arrow_up:
.../protocol/prometheus/network_protocol_prometheus.c	91.83% <100.00%> (+7.41%)	:arrow_up:
src/slab_allocator.c	95.01% <0.00%> (-3.07%)	:arrow_down:
src/spinlock.c	97.56% <0.00%> (-2.44%)	:arrow_down:

---

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 62ac35a...b082024. Read the comment docs.

[lgtm-com[bot]]

This pull request fixes 1 alert when merging b0820244bb376db94a6d571e63ebabe72fbfe791 into 62ac35a4deac928c884586b653800d5dfbf283ad - view on LGTM.com

fixed alerts:

• 1 for Wrong type of arguments to formatting function