Add build script

Introduced build script to build gemspec file.
This will be used by jenkins job to build and upload to rubygems.org.

Signed-off-by: Vijayan Balasubramanian <balasvij@amazon.com>

Author: VijayanB

.gitignore

@@ -18,4 +18,5 @@ vendor/
 /dockerfiles/bin/
 /dockerfiles/.env
 gem-private_key.pem
+builds/
 

build.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+# Copyright OpenSearch Contributors
+# SPDX-License-Identifier: Apache-2.0
+
+# This is intended to be run the  root directory. `release/build.sh`
+set -e
+
+GIT_ROOT=`git rev-parse --show-toplevel`
+
+cd $GIT_ROOT # We need to start from repository root
+
+rm -rf builds
+mkdir builds
+
+echo 'Building gem'
+gem build logstash-output-opensearch.gemspec
+
+echo 'Move Gem Location'
+mv -v logstash-output-opensearch*.gem $GIT_ROOT/builds/
+
+echo 'List of gems to be published: '
+ls -l $GIT_ROOT/builds