Fixup CHANGELOG.md to have correct changenotes for v1.44.75 and 74. (#…

…4514)

Fixes the SDK's changelog to have correct changenotes for v1.44.75 and v1.44.74.

CHANGELOG.md

@@ -1,15 +1,15 @@
 Release v1.44.75 (2022-08-11)
 ===
 
-Release v1.44.74 (2022-08-11)
-===
-
 ### Service Client Updates
 * `service/backupstorage`: Adds new service
 * `service/glue`: Updates service API
   * Add support for Python 3.9 AWS Glue Python Shell jobs
 * `service/privatenetworks`: Adds new service
 
+Release v1.44.74 (2022-08-11)
+===
+
 ### SDK Enhancements
 * `service/dynamodb/dynamodbattribute`: Add String method to UnixTime
   * Adds a `String` method to `UnixTime`, so that when structs with this field get logged it prints a human readable time.