Use short form of grep's quiet flag

[sachatelgenhof]

In one of our projects we are using Alpine Linux and the version of grep included does not recognize the long form of the quiet flag ('--quiet'). Perhaps it is better to use the shorthand form as that seems to be more supported (unconfirmed with other versions or OS though).

OS version: Alpine Linux v3.16 Linux: Linux 081aed2eda30 6.2.8-arch1-1 #1 SMP PREEMPT_DYNAMIC Wed, 22 Mar 2023 22:52:35 +0000 x86_64 Linux

Output from our smoke test script running under Alpine Linux

grep: unrecognized option: quiet
BusyBox v1.35.0 (2022-08-01 15:14:44 UTC) multi-call binary.
Usage: grep [-HhnlLoqvsrRiwFE] [-m N] [-A|B|C N] { PATTERN | -e PATTERN... | -f FILE... } [FILE]...
Search for PATTERN in FILEs (or stdin)
    -H  Add 'filename:' prefix
    -h  Do not add 'filename:' prefix
    -n  Add 'line_no:' prefix
    -l  Show only names of files that match
    -L  Show only names of files that don't match
    -c  Show only count of matching lines
    -o  Show only the matching part of line
    -q  Quiet. Return 0 if PATTERN is found, 1 otherwise
    -v  Select non-matching lines
    -s  Suppress open and read errors
    -r  Recurse
    -R  Recurse and dereference symlinks
    -i  Ignore case
    -w  Match whole words only
    -x  Match whole lines only
    -F  PATTERN is a literal (not regexp)
    -E  PATTERN is an extended regexp
    -m N    Match up to N times per file
    -A N    Print N lines of trailing context
    -B N    Print N lines of leading context
    -C N    Same as '-A N -B N'
    -e PTRN Pattern to match
    -f FILE Read pattern from file