Addressed lintian/shellcheck warnings#1471

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tuto193 wants to merge 5 commits intogreenbone:mainfrom tuto193:lintian_warnings_PL-52

+127-141

Commits on Mar 29, 2021

Replaced instances from non-standard "which"
Carlos A. Parra F
committed
Added missing warnings to 'cd' command in case of fail.
Carlos A. Parra F
committed
Replaced legacy .. with equivalent $(..).
Carlos A. Parra F
committed
Satisfied all remaining shellcheck warnings:
Carlos A. Parra F
committed
Added changelog entry.
Carlos A. Parra F
committed