Replace echo -e and echo -n with printf for macOS compatibility

[YCShen1010]

What this PR does / why we need it:
Some versions of macOS zsh do not recognize echo -e or echo -n flags, causing literal -e or -n to be printed in the output instead of the intended behavior.
Replaces all occurrences across the repo with their POSIX-portable printf equivalents:

echo -e → printf '%b\n'
echo -n → printf '%s'

Which issue(s) this PR fixes:
Fixes # https://github.ibm.com/IBMPrivateCloud/roadmap/issues/68532

[Daniel-Fan]

Thank you @YCShen1010

The test result looks positive!

➜  ✗ ./checker_tool/check_cpfs.sh --help
This is the main function
OPERATOR_NS is not set, use default namespace: ibm-common-services
You can set OPERATOR_NS by using the following command 'export OPERATOR_NS=<namespace>' 
Usage: check_cpfs.sh [OPTIONS]...

Accepted cli arguments are:
        [--help|-h], prints this help.
        [--all|-a], all cases will be ran.
        [--groups|-g <groups>], the case groups should be like --groups='group1,group2'.
        [--groups|-g -l], list the current supported groups.
        [--ignore-groups|-ng <groups>], skip the cases groups, like -ng group1,group2.
        [--cases|-c <cases>], the cases should be like --cases='case1,case2'.
        [--cases|-c -l], list the current supported cases.
        [--ignore-cases|-nc <cases>], skip the cases groups, like -nc case1,case2.
        [--output-file|-f <string>], name to use for the output file. Default name is 'results.json'