Out of the box coverage is 36.4% with spring-test

[SirAnimesh]

Using spring-test to mock HttpServletRequest and HttpServletResponse interfaces, improves the mocks used and quality of tests. This PR compares out of the box tests with no mocks (#4).

Also see coverage improvements gained by using Mockito mocks instead of spring-test mocks in #5.

Test creation summary for module: com.diffblue.pov:java-ee-servlet
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Total:                                              82 methods
46 tests created for:                               62 methods
19 partial tests created for:                       19 methods
                                                              
No tests created for:                               20 methods
    16 R011: Sandboxing policy violation                     
     3 R002: Missing observers                               
     1 R081: Exception in arrange section                    
                                                              
Diffblue tests cover 216 of 593 lines to cover (36.4%)
Manual tests cover 0 of 593 lines to cover (0.0%)

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Baeldung • How to Mock HttpServletRequest