replace run_cmd with run_shell_cmd in custom easyblock for CP2K (cp2k.py)

[branfosj]

(created using eb --new-pr)

• No use of EB_CP2K in easyconfigs or blocks

[branfosj]

Test report by @branfosj

Overview of tested easyconfigs (in order)

• SUCCESS Libint-2.7.2-GCC-11.3.0-lmax-6-cp2k.eb
• SUCCESS libvori-220621-GCCcore-11.3.0.eb
• SUCCESS CP2K-9.1-foss-2022a.eb

Build succeeded for 3 out of 3 (1 easyconfigs in total)
bear-pg0105u03a - Linux RHEL 8.6, x86_64, Intel(R) Xeon(R) Platinum 8360Y CPU @ 2.40GHz (icelake), Python 3.6.8
See https://gist.github.com/branfosj/91236048e3678b6db418d717130fe2c1 for a full test report.

[branfosj]

Test report by @branfosj

Overview of tested easyconfigs (in order)

• SUCCESS CP2K-9.1-foss-2022a.eb

Build succeeded for 1 out of 1 (1 easyconfigs in total)
bear-pg0105u03b - Linux RHEL 8.6, x86_64, Intel(R) Xeon(R) Platinum 8360Y CPU @ 2.40GHz (icelake), Python 3.6.8
See https://gist.github.com/branfosj/c2558380a474378bb5d996db11cb3b76 for a full test report.

[jfgrimm]

lgtm