chore: remove unused file assets_generate.go (#10638)

This file seem to be a remaining of https://github.com/prometheus/prometheus/pull/10220

Signed-off-by: Arunprasad Rajkumar <arajkuma@redhat.com>

web/ui/assets_generate.go

@@ -1,39 +0,0 @@
-// Copyright 2018 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-//go:build ignore
-// +build ignore
-
-package main
-
-import (
-	"log"
-	"time"
-
-	"github.com/shurcooL/vfsgen"
-
-	"github.com/prometheus/prometheus/util/modtimevfs"
-	"github.com/prometheus/prometheus/web/ui"
-)
-
-func main() {
-	fs := modtimevfs.New(ui.Assets, time.Unix(1, 0))
-	err := vfsgen.Generate(fs, vfsgen.Options{
-		PackageName:  "ui",
-		BuildTags:    "builtinassets",
-		VariableName: "Assets",
-	})
-	if err != nil {
-		log.Fatalln(err)
-	}
-}