Remove deprecated GsonHelper class

Signed-off-by: Paolo Di Tommaso <paolo.ditommaso@gmail.com>

Author: pditommaso

modules/nf-commons/src/main/nextflow/util/GsonHelper.groovy

@@ -40,8 +40,6 @@ import nextflow.serde.gson.GsonEncoder
 @CompileStatic
 class LinUtils {
 
-    private static final String[] EMPTY_ARRAY = new String[] {}
-
     /**
      * Get a lineage record or fragment from the Lineage store.
      *

modules/nf-commons/src/test/nextflow/util/GsonHelperTest.groovy

@@ -34,7 +34,7 @@ import nextflow.fusion.FusionConfig
 import nextflow.fusion.FusionToken
 import nextflow.platform.PlatformHelper
 import nextflow.plugin.Priority
-import nextflow.util.GsonHelper
+import nextflow.serde.gson.GsonEncoder
 import nextflow.util.Threads
 import org.pf4j.Extension
 /**
@@ -269,7 +269,8 @@ class TowerFusionToken implements FusionToken {
      * @return The resulting HttpRequest object
      */
     private HttpRequest makeHttpRequest(GetLicenseTokenRequest req) {
-        final body = HttpRequest.BodyPublishers.ofString( GsonHelper.toJson(req) )
+        final gson = new GsonEncoder<GetLicenseTokenRequest>() {}
+        final body = HttpRequest.BodyPublishers.ofString( gson.encode(req) )
         return HttpRequest.newBuilder()
             .uri(URI.create("${endpoint}/${LICENSE_TOKEN_PATH}").normalize())
             .header('Content-Type', 'application/json')
@@ -298,7 +299,8 @@ class TowerFusionToken implements FusionToken {
      * @throws JsonSyntaxException if the JSON string is not well-formed
      */
     protected static GetLicenseTokenResponse parseLicenseTokenResponse(String json) throws JsonSyntaxException {
-        return GsonHelper.fromJson(json, GetLicenseTokenResponse.class)
+        final gson = new GsonEncoder<GetLicenseTokenResponse>() {}
+        return gson.decode(json)
     }
 
     /**

modules/nf-lineage/src/main/nextflow/lineage/LinUtils.groovy

@@ -1,21 +1,21 @@
 package io.seqera.tower.plugin
 
+import static com.github.tomakehurst.wiremock.client.WireMock.*
+
 import java.time.Instant
 import java.time.temporal.ChronoUnit
 
 import com.github.tomakehurst.wiremock.WireMockServer
 import com.github.tomakehurst.wiremock.client.WireMock
 import com.github.tomakehurst.wiremock.stubbing.Scenario
+import com.google.gson.GsonBuilder
 import io.seqera.tower.plugin.exception.UnauthorizedException
 import nextflow.Global
 import nextflow.Session
 import nextflow.SysEnv
-import nextflow.util.GsonHelper
+import nextflow.serde.gson.InstantAdapter
 import spock.lang.Shared
 import spock.lang.Specification
-
-import static com.github.tomakehurst.wiremock.client.WireMock.*
-
 /**
  * Test cases for the TowerFusionEnv class.
  *
@@ -44,6 +44,13 @@ class TowerFusionEnvTest extends Specification {
         SysEnv.pop()      // <-- restore the system host env
     }
 
+    static String toJson(Object obj) {
+        new GsonBuilder()
+            .registerTypeAdapter(Instant, new InstantAdapter())
+            .create()
+            .toJson(obj)
+    }
+
     def 'should return the endpoint from the config'() {
         given: 'a session'
         Global.session = Mock(Session) {
@@ -263,7 +270,7 @@ class TowerFusionEnvTest extends Specification {
 
         and: 'a mock endpoint returning a valid token'
         final now = Instant.now()
-        final expirationDate = GsonHelper.toJson(now.plus(1, ChronoUnit.DAYS))
+        final expirationDate = toJson(now.plus(1, ChronoUnit.DAYS))
         wireMockServer.stubFor(
             WireMock.post(urlEqualTo("/license/token/"))
                 .withHeader('Authorization', equalTo('Bearer abc123'))
@@ -306,7 +313,7 @@ class TowerFusionEnvTest extends Specification {
 
         and: 'a mock endpoint returning a valid token'
         final now = Instant.now()
-        final expirationDate = GsonHelper.toJson(now.plus(1, ChronoUnit.DAYS))
+        final expirationDate = toJson(now.plus(1, ChronoUnit.DAYS))
         wireMockServer.stubFor(
             WireMock.post(urlEqualTo("/license/token/"))
                 .withHeader('Authorization', equalTo('Bearer abc123'))
@@ -354,7 +361,7 @@ class TowerFusionEnvTest extends Specification {
         and: 'prepare stubs'
 
         final now = Instant.now()
-        final expirationDate = GsonHelper.toJson(now.plus(1, ChronoUnit.DAYS))
+        final expirationDate = toJson(now.plus(1, ChronoUnit.DAYS))
 
         // 1️⃣ First attempt: /license/token/ fails with 401
         wireMockServer.stubFor(