Override postgresql version defined by spring-boot-dependencies (#1416)

## 🎫 Ticket

https://jira.cms.gov/browse/AB2D-6397

## 🛠 Changes
- In the parent POM, rename property from `postgres.version` to
`postgresql.version` to properly override version defined in
`spring-boot-dependencies`.
- Bump postgresql version to 42.7.4 to be consistent with #1412

## ℹ️ Context

The postgres version defined by `spring-boot-dependencies` is 42.3.8.
Snyk flags this version as vulnerable.

Modules **common** and **job** override this version to 42.7.3. However,
when another module imports one of these modules, Maven does not select
this overridden version and instead selects the version defined by
`spring-boot-dependencies`.

## 🧪 Validation

Running `mvn dependency:tree` on **main** shows different versions being
used for different modules.
On the feature branch, the same version is used across all modules. 


![image](https://github.com/user-attachments/assets/720540df-5485-4f97-ad1f-17df44319aab)

common/pom.xml

@@ -54,7 +54,7 @@
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>
-            <version>${postgres.version}</version>
+            <version>${postgresql.version}</version>
         </dependency>
         <dependency>
             <groupId>org.liquibase</groupId>

job/pom.xml

@@ -52,7 +52,7 @@
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>
-            <version>${postgres.version}</version>
+            <version>${postgresql.version}</version>
         </dependency>
     </dependencies>
 

pom.xml

@@ -35,7 +35,7 @@
         <logback-encoder.version>7.3</logback-encoder.version>
         <testcontainers.version>1.18.3</testcontainers.version>
         <newrelic.version>8.15.0</newrelic.version>
-        <postgres.version>42.7.3</postgres.version>
+        <postgresql.version>42.7.4</postgresql.version>
         <spring-cloud-aws.version>2.4.4</spring-cloud-aws.version>
 
         <!-- Maven plugin versions -->