Try tricking Jenkins into using

Jenkinsfile

@@ -1,6 +1,7 @@
 #!/usr/bin/env groovy
 
 node {
+    withEnv(["PATH=$HOME/bin:$PATH"]) {
         stage('checkout') {
             checkout scm
         }
@@ -21,7 +22,7 @@ node {
         stage('backend tests') {
             try {
                 sh "./gradlew test -PnodeInstall --no-daemon"
-        } catch(err) {
+            } catch (err) {
                 throw err
             } finally {
                 junit '**/build/**/TEST-*.xml'
@@ -31,7 +32,7 @@ node {
         stage('frontend tests') {
             try {
                 sh "./gradlew npm_run_test -PnodeInstall --no-daemon"
-        } catch(err) {
+            } catch (err) {
                 throw err
             } finally {
                 junit '**/build/test-results/TESTS-*.xml'
@@ -48,4 +49,5 @@ node {
                 sh "./gradlew sonarqube --no-daemon"
             }
         }
+    }
 }

gradle.properties

@@ -2,7 +2,7 @@ rootProject.name=hsadmin-ng
 profile=dev
 
 # Build properties
-node_version=10.15.0
+node_version=10.15.3
 npm_version=6.4.1
 yarn_version=1.13.0