fix: no throw on unknown config value

[amphro]

Right now, old versions of the core library will throw if there is an unknown key in the config file. If a new key is added in future versions of core, the old version doesn't know about it and will throw. THis prevents this from happening in the future.

@W-8880355@

[codecov-io]

Codecov Report

Merging #372 (49618db) into main (934e34c) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #372   +/-   ##
=======================================
  Coverage   82.56%   82.56%           
=======================================
  Files          38       38           
  Lines        3189     3189           
  Branches      555      556    +1     
=======================================
  Hits         2633     2633           
  Misses        341      341           
  Partials      215      215           

Impacted Files	Coverage Δ
src/config/config.ts	73.58% <100.00%> (ø)

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