add 7.6.0 to the azure devops pipeline (#4438) (#4449)

* add 7.6.0 to the azure devops pipeline
* fix declaring es75 twice

Co-authored-by: Martijn Laarman <[email protected]>

Author: github-actions[bot]

azure-pipelines.yml

@@ -78,6 +78,8 @@ jobs:
         esVersion: '7.4.0'
       es75:
         esVersion: '7.5.0'
+      es76:
+        esVersion: '7.6.0'
       latest7:
         esVersion: 'latest-7'
   steps:
@@ -112,6 +114,8 @@ jobs:
           esVersion: '7.4.0'
         es75:
           esVersion: '7.5.0'
+        es76:
+          esVersion: '7.6.0'
         latest7:
           esVersion: 'latest-7'
   steps: