dynamic port for UI from 8080 up (8081 etc) (#3042)

# Description of Changes

Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

src/test/java/stirling/software/SPDF/SPDFApplicationTest.java

@@ -31,7 +31,7 @@ public class SPDFApplicationTest {
     private ApplicationProperties applicationProperties;
 
     @InjectMocks
-    private SPDFApplication SPDFApplication;
+    private SPDFApplication sPDFApplication;
 
     @BeforeEach
     public void setUp() {
@@ -49,8 +49,4 @@ public class SPDFApplicationTest {
         assertEquals("8080", SPDFApplication.getStaticPort());
     }
 
-    @Test
-    public void testGetNonStaticPort() {
-        assertEquals("8080", SPDFApplication.getNonStaticPort());
-    }
 }