fix: use assumeRoleWithWebIdentity when using IRSA (#416)

* add support for assumeRoleWithWebIdentity when used on AWS Fargate IRSA

* removed trailing spaces as detected by eslint

Author: lukaszbudnik

config/aws-config.js

@@ -6,6 +6,7 @@ const clonedeep = require('lodash.clonedeep')
 const merge = require('lodash.merge')
 
 const localstack = process.env.LOCALSTACK || 0
+const webIdentity = process.env.AWS_WEB_IDENTITY_TOKEN_FILE || 0
 
 let secretsManagerConfig = {}
 let systemManagerConfig = {}
@@ -44,6 +45,17 @@ module.exports = {
   },
   assumeRole: (assumeRoleOpts) => {
     const sts = new AWS.STS(stsConfig)
+    if (webIdentity) {
+      return new Promise((resolve, reject) => {
+        sts.assumeRoleWithWebIdentity(assumeRoleOpts, (err, res) => {
+          if (err) {
+            return reject(err)
+          }
+          resolve(res)
+        })
+      })
+    }
+
     return new Promise((resolve, reject) => {
       sts.assumeRole(assumeRoleOpts, (err, res) => {
         if (err) {