added missing license header

Author: Roy Razon

build_utils/fix_coverage_thresholds.js

@@ -1,4 +1,19 @@
 #!/usr/bin/env node
+/*
+*                      Copyright 2020 Salto Labs Ltd.
+*
+* 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.
+*/
 
 const fs = require('fs')
 const fsp = fs.promises