server: switch to compiler warning for use of deprecated APIs

This will give some time to fix the usage of deprecated APIs.

Change-Id: I1a7629d6f8b874be6ecc6495bcac2fa2b3e76fe9
Signed-off-by: Bernd Hufmann <Bernd.Hufmann@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/c/tracecompass.incubator/org.eclipse.tracecompass.incubator/+/191793
Tested-by: Trace Compass Bot <tracecompass-bot@eclipse.org>
Tested-by: Patrick Tasse <patrick.tasse@gmail.com>
Reviewed-by: Patrick Tasse <patrick.tasse@gmail.com>

trace-server/org.eclipse.tracecompass.incubator.trace.server.jersey.rest.core/.settings/org.eclipse.jdt.core.prefs

@@ -1,4 +1,5 @@
 eclipse.preferences.version=1
+org.eclipse.jdt.core.builder.annotationPath.allLocations=disabled
 org.eclipse.jdt.core.codeComplete.argumentPrefixes=
 org.eclipse.jdt.core.codeComplete.argumentSuffixes=
 org.eclipse.jdt.core.codeComplete.fieldPrefixes=f
@@ -34,7 +35,7 @@ org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
 org.eclipse.jdt.core.compiler.problem.autoboxing=ignore
 org.eclipse.jdt.core.compiler.problem.comparingIdentical=error
 org.eclipse.jdt.core.compiler.problem.deadCode=error
-org.eclipse.jdt.core.compiler.problem.deprecation=error
+org.eclipse.jdt.core.compiler.problem.deprecation=warning
 org.eclipse.jdt.core.compiler.problem.deprecationInDeprecatedCode=disabled
 org.eclipse.jdt.core.compiler.problem.deprecationWhenOverridingDeprecatedMethod=enabled
 org.eclipse.jdt.core.compiler.problem.discouragedReference=warning