Update changelog of 3.1.4

Signed-off-by: chenwany <[email protected]>

Author: chenwany

CHANGELOG.md

@@ -7,7 +7,7 @@ This file is used to list changes made in each version of the AWS ParallelCluste
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 **CHANGES**
-- Upgrade Slurm to version 21.08.8.
+- Upgrade Slurm to version 21.08.8-2.
 
 3.1.3
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