Improve compatibility by replacing use of seq with a native for-loop

Closes gh-21068

spring-boot-project/spring-boot-tools/spring-boot-loader-tools/src/main/resources/org/springframework/boot/loader/tools/launch.script

@@ -223,7 +223,7 @@ stop() {
 
 do_stop() {
   kill "$1" &> /dev/null || { echoRed "Unable to kill process $1"; return 1; }
-  for i in $(seq 1 $STOP_WAIT_TIME); do
+  for ((i = 1; i <= STOP_WAIT_TIME; i++)); do
     isRunning "$1" || { echoGreen "Stopped [$1]"; rm -f "$2"; return 0; }
     [[ $i -eq STOP_WAIT_TIME/2 ]] && kill "$1" &> /dev/null
     sleep 1
@@ -241,7 +241,7 @@ force_stop() {
 
 do_force_stop() {
   kill -9 "$1" &> /dev/null || { echoRed "Unable to kill process $1"; return 1; }
-  for i in $(seq 1 $STOP_WAIT_TIME); do
+  for ((i = 1; i <= STOP_WAIT_TIME; i++)); do
     isRunning "$1" || { echoGreen "Stopped [$1]"; rm -f "$2"; return 0; }
     [[ $i -eq STOP_WAIT_TIME/2 ]] && kill -9 "$1" &> /dev/null
     sleep 1