Switch to Gradle 7.4

[Jeeppler]

Situation

Currently we cannot update to gradle 7.x

Reasons

Prepare for Gradle 7.0. Gradle 7.0 will have several breaking changes:

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.7.1/userguide/command_line_interface.html#sec:command_line_warnings

To show where changes are necessary use:

./gradlew --warning-mode all

Wanted

We want to use gradle version 7.4 and have an updated gradle wrapper as well

Solution

• Apply necessary changes in Make build gradle 7.0 compatible #1085 and after this, setup the gradle version to 7.4
• Also update the gradle wrapper parts to 7.4

[Jeeppler]

SpringBoot 2.5 will support Gradle 7.0: https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-2.5.0-RC1-Release-Notes#gradle-7x-support

Issue regarding the upgrade to SpringBoot 2.5: #609

[de-jcup]

With last commit I got following error messages inside build:

> Task :sechub-testframework:build
> Task :sechub-doc:openapi3
> Task :sechub-doc:generateOpenapi

> Task :sechub-developertools:buildDeveloperAdminUI FAILED
FAILURE: Build failed with an exception.


* What went wrong:
Execution failed for task ':sechub-developertools:buildDeveloperAdminUI'.
> Entry META-INF/LICENSE.txt is a duplicate but no duplicate handling strategy has been set. Please refer to https://docs.gradle.org/7.4/dsl/org.gradle.api.tasks.Copy.html#org.gradle.api.tasks.Copy:duplicatesStrategy for details.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org/

BUILD FAILED in 4m 2s
Deprecated Gradle features were used in this build, making it incompatible with Gradle 8.0.

You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.

See https://docs.gradle.org/7.4/userguide/command_line_interface.html#sec:command_line_warnings
336 actionable tasks: 334 executed, 2 up-to-date
Error: Process completed with exit code 1.

Solution :
will use
duplicatesStrategy = DuplicatesStrategy.EXCLUDE to contain duplicated license text files (which is correct in this case). So output as before.