Remove non-supported dependency

[dzahariev]

The https://github.com/ronmamo/reflections seem to not be maintained for more than a year.
The fork: https://github.com/aschoerk/reflections8 provides the same functionality, but removes dependency to Guava in flavour to Java 8 Streams APIs.
Currently Guava 20.0 have 2 security issues CVE-2018-10237 and CVE-2020-8908 that will be gone after this adoption.

The adoption seem to be pretty straightforward - dependency is changed to:

		<dependency>
			<groupId>net.oneandone.reflections8</groupId>
			<artifactId>reflections8</artifactId>
			<version>0.11.5</version>
		</dependency>

And imports of packages org.reflections.* are renamed to org.reflections8.*.

The tests pass without issues after that:

[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] odata-jpa .......................................... SUCCESS [  0.590 s]
[INFO] odata-jpa-annotation ............................... SUCCESS [  1.078 s]
[INFO] odata-jpa-test ..................................... SUCCESS [  6.157 s]
[INFO] odata-jpa-metadata ................................. SUCCESS [ 12.096 s]
[INFO] odata-jpa-processor ................................ SUCCESS [ 26.294 s]
[INFO] odata-jpa-coverage ................................. SUCCESS [  1.638 s]
[INFO] odata-jpa-spring-support ........................... SUCCESS [  0.027 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 47.988 s
[INFO] Finished at: 2021-04-15T20:33:18+03:00
[INFO] Final Memory: 31M/128M
[INFO] ------------------------------------------------------------------------