Fix build.gradle

Signed-off-by: Ryan Wang <i@ryanc.cc>

Author: ruibaby

build.gradle

@@ -1,7 +1,7 @@
 plugins {
     id 'java'
     id "io.freefair.lombok" version "8.0.1"
-    id "com.github.node-gradle.node" version "5.0.0"
+    id "com.github.node-gradle.node" version "7.0.2"
     id "run.halo.plugin.devtools" version "0.0.7"
 }
 
@@ -31,13 +31,20 @@ node {
     nodeProjectDir = file("${project.projectDir}")
 }
 
-task buildFrontend(type: PnpmTask) {
+tasks.register('buildFrontend', PnpmTask) {
     args = ['build:packages']
+    dependsOn('installDepsForUI')
+}
+
+tasks.register('installDepsForUI', PnpmTask) {
+    args = ['install']
 }
 
 build {
     // build frontend before build
-    tasks.getByName('compileJava').dependsOn('buildFrontend')
+    tasks.named('compileJava').configure {
+        dependsOn('buildFrontend')
+    }
 }
 
 halo {