Upgrade Issues - OSGi Manifest

[AlexC]

Hello all, 

I want upgrade our JIRA version to 8.20.17 (DC version more exactly). However, I've some issues with one plugin made by my company, and I don't know how to resolve it. 
I tried so many things but it didn't work (I changed the JDK version, built the plugin in Eclipse, updated the pom.xml file, .....)

Here is the error :

2023-02-22 15:52:37,181+0100 UpmAsynchronousTaskManager:thread-2 ERROR 609x3096x1 XX.X.XX.X /rest/plugins/1.0/ [c.a.plugin.loaders.ScanningPluginLoader] Unable to deploy plugin '${project.groupId}.${project.artifactId}' from 'Unit: <Path_To_The_Plugin>.jar (1677077557159)'.

2023-02-22 15:52:37,182+0100 UpmAsynchronousTaskManager:thread-2 ERROR 609x3096x1 XX.X.XX.XXX /rest/plugins/1.0/ [c.a.plugin.loaders.ScanningPluginLoader] Because of the following exception:
com.atlassian.plugin.PluginParseException: Unable to process plugin to generate OSGi manifest
        at com.atlassian.plugin.osgi.factory.transform.stage.GenerateManifestStage.execute(GenerateManifestStage.java:213)
 .......

2023-02-22 15:52:37,185+0100 UpmAsynchronousTaskManager:thread-2 WARN 609x3096x1 X.XX.XX.X /rest/plugins/1.0/ [c.a.u.core.install.DefaultPluginInstallationService] Plugin installation failed: Unknown error, plugin not installed

2023-02-22 15:52:37,185+0100 UpmAsynchronousTaskManager:thread-2 WARN 609x3096x1 XX.XX.X.X /rest/plugins/1.0/ [c.a.u.core.install.DefaultPluginInstallationService] com.atlassian.upm.spi.PluginInstallException: Unknown error, plugin not installed
com.atlassian.upm.spi.PluginInstallException: Unknown error, plugin not installed
        at com.atlassian.upm.core.install.AbstractPluginInstallHandler.installArtifact(AbstractPluginInstallHandler.java:116)
      ........

Have you got any idea ? 

If you need any additionals information, tell me.

Regards, 

Alexandre