Remove Maven config that exclude tomcat dependency under Springboot3 …

[alvinkwok1]

…module

What kind of change does this PR introduce? (check at least one)

• [ ] Bugfix
• [ ] Feature
• [ ] Code style
• [ ] Refactor
• [ ] Doc
• [x] Other, please describe:

The description of the PR:

Remove Maven config that exclude tomcat dependency under Springboot3 module

Fixes 4.2.0的dynamic-datasource-spring-boot3-starter/pom.xml中不应更改web容器为undertow，应由用户自己决定 #587 Other information:

[alvinkwok1]

Call @huayanYu to help review.