test: drop the mawk-incompatible expression

The three-argument match() is a GNU AWK extension, thus breaking the
compatibility with mawk (used on Ubuntu/Debian, for example). Let's
replace it with a (hopefully) more portable sed expression to drop the
inadvertently introduced gawk dependency.

Fixes: #19957

hwdb.d/60-keyboard.hwdb

@@ -623,6 +623,8 @@ evdev:atkbd:dmi:bvn*:bvr*:bd*:svnHewlett-Packard*:pnHPLicrice:*
 # HP EliteBook
 evdev:atkbd:dmi:bvn*:bvr*:bd*:svnHewlett-Packard*:pnHPEliteBook*:*
 evdev:atkbd:dmi:bvn*:bvr*:bd*:svnHP*:pnHPEliteBook*:*
+# HP Elite Dragonfly
+evdev:atkbd:dmi:bvn*:bvr*:bd*:svnHP*:pnHPEliteDragonfly*:*
 # HP ProBook 440 G2
 evdev:atkbd:dmi:bvn*:bvr*:bd*:svnHewlett-Packard*:pnHP440G2:*
 # HP ProBook

test/test-functions

@@ -2036,7 +2036,7 @@ inst_rule_programs() {
     local rule="${1:?}"
     local prog bin
 
-    awk 'match($0, /PROGRAM==?"([^ "]+)/, m) { print m[1]; }' "$rule" | while read -r prog; do
+    sed -rn 's/^.*?PROGRAM==?"([^ "]+).*$/\1/p' "$rule" | while read -r prog; do
         if [ -x "/lib/udev/$prog" ]; then
             bin="/lib/udev/$prog"
         else