BAEL-5900: Using Firebase Cloud Messaging in SpringBoot Applications (#13102)

* [BAEL-4849] Article code

* [BAEL-4968] Article code

* [BAEL-4968] Article code

* [BAEL-4968] Article code

* [BAEL-4968] Remove extra comments

* [BAEL-5258] Article Code

* [BAEL-2765] PKCE Support for Secret Clients

* [BAEL-5698] Article code

* [BAEL-5698] Article code

* [BAEL-5900] Initial commit

gcp-firebase/pom.xml

@@ -0,0 +1,48 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-boot-2</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-boot-2</relativePath>
+    </parent>
+  <artifactId>gcp-firebase</artifactId>
+  
+  <properties>
+    <firebase-admin.version>9.1.1</firebase-admin.version>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>com.google.firebase</groupId>
+      <artifactId>firebase-admin</artifactId>
+      <version>${firebase-admin.version}</version>
+    </dependency>
+    
+    
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-web</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-configuration-processor</artifactId>
+        <optional>true</optional>
+    </dependency>
+  </dependencies>
+  
+  
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+</project>