Improve error checking so that the scripts stop as soon as an error is found

[rhness]

Improve error checking so that the scripts stop as soon as an error is found.

Example:

Mon Jun 16 05:51:11 GMT 2025 BuildRCApps.sh Copy and link Windows built RCA
Mon Jun 16 05:51:11 GMT 2025 BuildRCApps.sh RCA release number 1.1.0_RC13
Mon Jun 16 05:51:11 GMT 2025 BuildRCApps.sh Run regression tests
./BuildRCApps.sh: line 85: ./target/bin/gerstf: EDC5111I Permission denied.
./BuildRCApps.sh: line 86: cd: out: EDC5129I No such file or directory.
cat: fmoverview.txt: EDC5129I No such file or directory.
send '05.51.12 Generating the tag scripts and JCL...               ' user(RHNESS)
Mon Jun 16 05:51:12 GMT 2025 GenTag.sh Start generation of tagging scripts
Mon Jun 16 05:51:15 GMT 2025 GenTag.sh Performance Engine tagging scripts generated
Mon Jun 16 05:51:15 GMT 2025 Build.sh Build process completed for PM4.18.109.B0042