Заменил используемую СУБД Postgres на MySQL

https://spring.io/guides/gs/accessing-data-mysql

pom.xml

@@ -26,12 +26,10 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-mustache</artifactId>
         </dependency>
-
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
-
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-devtools</artifactId>
@@ -43,7 +41,6 @@
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>
-
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jpa</artifactId>
@@ -55,8 +52,8 @@
             <optional>true</optional>
         </dependency>
         <dependency>
-            <groupId>org.postgresql</groupId>
-            <artifactId>postgresql</artifactId>
+            <groupId>com.mysql</groupId>
+            <artifactId>mysql-connector-j</artifactId>
             <scope>runtime</scope>
         </dependency>
     </dependencies>
@@ -69,5 +66,4 @@
             </plugin>
         </plugins>
     </build>
-
 </project>