Spring analyzer improvements (fix uncaught exception, add shadowJar task, fix dynamic resources not being found on the classpath)

[IlyaMuravjov]

Description

• Remove UtBotSpringShutdownException because it gets caught by Spring
• For dynamically created Spring resources replace "classpath:" resource-loading prefix with "file:"
• Configure shadowJar Gradle task for spring-analyzer
  • The resulting jar file is utbot-spring-analyzer\build\libs\utbot-spring-analyzer-2023.03-SNAPSHOT-all.jar

How to test

Should not be tested standalone, just as a part of Spring support 1st phase.

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