Minor improvements in check_certificates wrapper script.

tools/check_certificates

@@ -6,6 +6,9 @@
 # See https://github.com/Matty9191/ssl-cert-check for details.
 #
 # Author: Kovács Zoltán <kovacsz@marcusconsulting.hu>
+# 2026-05-04 v0.2
+# mod: It now also checks the dependencies of the worker script.
+# fix: Suppresses error output during 'which' calls.
 # 2026-02-16 v0.1 Initial release
 
 # Accepted environment variables and their defaults.
@@ -27,12 +30,13 @@ MSG_MISSINGYML="Fatal: didn't find the docker-compose.yml file"
 LANG=C
 LC_ALL=C
 
-# Checks the dependencies.
+# Checks the dependencies (including the worker script's).
 TR=$(which tr 2>/dev/null)
 if [ -z "$TR" ]; then echo "$MSG_MISSINGDEP tr."; exit 1 ; fi
-for item in basename dirname find readlink
+for item in basename dirname find readlink \
+            awk date grep mktemp openssl printf
 do
-    if [ -n "$(which $item)" ]
+    if [ -n "$(which $item 2>/dev/null)" ]
     then export $(echo $item | "$TR" '[:lower:]' '[:upper:]' | "$TR" '-' '_')=$(which $item)
     else echo "$MSG_MISSINGDEP $item." >&2; exit 1; fi
 done