postinst: improve wording

add missing `the` in front of name, remove redundant `using systemd`
when already using `systemctl`

Signed-off-by: Mae Dartmann <[email protected]>

 Changes to be committed:
	modified:   scripts/pkg/build_templates/opensearch-dashboards/deb/debian/postinst
	modified:   scripts/pkg/build_templates/opensearch/deb/debian/postinst

Author: Mae Dartmann

scripts/pkg/build_templates/opensearch-dashboards/deb/debian/postinst

@@ -28,9 +28,9 @@ fi
 systemd-tmpfiles --create opensearch-dashboards.conf
 
 # Messages
-echo "### NOT starting on installation, please execute the following statements to configure opensearch-dashboards service to start automatically using systemd"
+echo "### NOT starting on installation, please execute the following command to configure the opensearch-dashboards service to start automatically"
 echo " systemctl enable opensearch-dashboards.service"
-echo "### You can start opensearch-dashboards service by executing"
+echo "### You can start the opensearch-dashboards service by executing"
 echo " systemctl start opensearch-dashboards.service"
 
 # Set owner

scripts/pkg/build_templates/opensearch/deb/debian/postinst

@@ -47,9 +47,9 @@ sysctl -p /usr/lib/sysctl.d/opensearch.conf > /dev/null 2>&1
 systemd-tmpfiles --create opensearch.conf
 
 # Messages
-echo "### NOT starting on installation, please execute the following statements to configure opensearch service to start automatically using systemd"
+echo "### NOT starting on installation, please execute the following command to configure the opensearch service to start automatically"
 echo " systemctl enable opensearch.service"
-echo "### You can start opensearch service by executing"
+echo "### You can start the opensearch service by executing"
 echo " systemctl start opensearch.service"
 
 if [ -d ${product_dir}/plugins/opensearch-security ]; then