Revert "(CI): added build for c7"

This reverts commit b2244e19.
2 jobs from master in 7 minutes 30 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #5425
rx-build
build and public

04:25

 
  Test
failed #5426
rx-tests
testsuite

03:05

 
Name Stage Failure
failed
testsuite Test
No job trace