build: use fully qualified path names for deps (#30414)

This aligns the code with the GN Style Guide: https://gn.googlesource.com/gn/+/refs/heads/main/docs/style_guide.md#deps

Signed-off-by: Darshan Sen <darshan.sen@postman.com>

build/npm.gni

@@ -5,8 +5,8 @@ template("npm_action") {
 
   action("npm_pre_flight_" + target_name) {
     inputs = [
-      "package.json",
-      "yarn.lock",
+      "//electron/package.json",
+      "//electron/yarn.lock",
     ]
     script = "//electron/build/npm-run.py"
 

build/webpack/webpack.gni

@@ -36,7 +36,7 @@ template("webpack_build") {
           rebase_path("$target_gen_dir/buildflags/buildflags.h"),
       "--env.mode=" + mode,
     ]
-    deps += [ "buildflags" ]
+    deps += [ "//electron/buildflags" ]
 
     outputs = [ invoker.out_file ]
   }