Apply suggestions from code review from @per1234

Co-Authored-By: sandeepmistry <sandeep.mistry@gmail.com>

Author: per1234

examples/Google Cloud Platform IoT Core/GCP_IoT_Core_GSM/GCP_IoT_Core_GSM.ino

@@ -7,7 +7,7 @@
 
   It publishes a message every 5 seconds to "/devices/{deviceId}/state" topic
   and subscribes to messages on the "/devices/{deviceId}/config" and
-  "/devices/{deviceId}/commands/# topics.
+  "/devices/{deviceId}/commands/#" topics.
 
   The circuit:
   - MKR GSM 1400 board
@@ -107,7 +107,7 @@ void connectGSM() {
 }
 
 void connectMQTT() {
-  Serial.print("Attempting to MQTT broker: ");
+  Serial.print("Attempting to connect to MQTT broker: ");
   Serial.print(broker);
   Serial.println(" ");
 

examples/Google Cloud Platform IoT Core/GCP_IoT_Core_GSM/arduino_secrets.h

@@ -1,6 +1,6 @@
 // GSM settings
 #define SECRET_PINNUMBER     ""
-#define SECRET_GPRS_APN      "GPRS_APN" // replace your GPRS APN
+#define SECRET_GPRS_APN      "GPRS_APN" // replace with your GPRS APN
 #define SECRET_GPRS_LOGIN    "login"    // replace with your GPRS login
 #define SECRET_GPRS_PASSWORD "password" // replace with your GPRS password
 

examples/Google Cloud Platform IoT Core/GCP_IoT_Core_NB/GCP_IoT_Core_NB.ino

@@ -7,7 +7,7 @@
 
   It publishes a message every 5 seconds to "/devices/{deviceId}/state" topic
   and subscribes to messages on the "/devices/{deviceId}/config" and
-  "/devices/{deviceId}/commands/# topics.
+  "/devices/{deviceId}/commands/#" topics.
 
   The circuit:
   - MKR NB 1500 board
@@ -104,7 +104,7 @@ void connectNB() {
 }
 
 void connectMQTT() {
-  Serial.print("Attempting to MQTT broker: ");
+  Serial.print("Attempting to connect to MQTT broker: ");
   Serial.print(broker);
   Serial.println(" ");
 

examples/Google Cloud Platform IoT Core/GCP_IoT_Core_WiFi/GCP_IoT_Core_WiFi.ino

@@ -7,7 +7,7 @@
 
   It publishes a message every 5 seconds to "/devices/{deviceId}/state" topic
   and subscribes to messages on the "/devices/{deviceId}/config" and
-  "/devices/{deviceId}/commands/# topics.
+  "/devices/{deviceId}/commands/#" topics.
 
   The circuit:
   - Arduino MKR WiFi 1010 or MKR1000
@@ -101,7 +101,7 @@ void connectWiFi() {
 }
 
 void connectMQTT() {
-  Serial.print("Attempting to MQTT broker: ");
+  Serial.print("Attempting to connect to MQTT broker: ");
   Serial.print(broker);
   Serial.println(" ");