Minor pom.xml refactor

[SylvainJuge]

• remove useless groupId for base plugins
• pin plugin versions to <pluginManagement>
• fix broken path when copying LICENSE file

[apmmachine]

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#### Build stats * Start Time: 2022-08-01T15:54:58.686+0000 * Duration: 8 min 1 sec #### Test stats :test_tube: | Test | Results | | ------------ | :-----------------------------: | | Failed | 0 | | Passed | 243 | | Skipped | 0 | | Total | 243 |

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