sdk: Add --jobs parameter in build/test bpf

[joncinque]

Problem

It's impossible to set the number of jobs to build-bpf and test-bpf, since --jobs figures as a pre--- parameter for cargo build and cargo test. The extra parsing to pass the post -- parameters also doesn't pass --jobs correctly, and we're having build failures on cargo test-bpf for the SPL governance program due to memory consumption.

Summary of Changes

Add a --jobs flag to both build-bpf and test-bpf. The parsing looks a bit wonky since it validates it as a number, then stores it as a string. This is done to make it easier to pass into cargo.

[t-nelson]

ah! that'll do it. nice find!

[codecov]

Codecov Report

Merging #24359 (b085f61) into master (2456a7b) will increase coverage by 0.0%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #24359   +/-   ##
=======================================
  Coverage    82.1%    82.1%           
=======================================
  Files         582      582           
  Lines      162385   162385           
=======================================
+ Hits       133406   133414    +8     
+ Misses      28979    28971    -8