[CODEOWNERS] Remove retired label (Azure#48682)

The focus of these changes is to remove a the `Data Lake Storage Gen1` label that is associated with a retired service no longer under support.

Author: jsquire

.github/CODEOWNERS

@@ -450,9 +450,6 @@
 # ServiceLabel: %Data Lake
 # ServiceOwners:                                                   @sumantmehtams
 
-# ServiceLabel: %Data Lake Storage Gen1
-# ServiceOwners:                                                   @sumantmehtams @seanmcc-msft @amnguye @jaschrep-msft @jalauzon-msft @nickliu-msft
-
 # ServiceLabel: %Data Lake Storage Gen2
 # ServiceOwners:                                                   @sumantmehtams @seanmcc-msft @amnguye @jaschrep-msft @jalauzon-msft @nickliu-msft