s/Get(Master|Replica)X/Get\1/g (#29520)

Drop the legacy `X` suffix from `GetMasterX` and `GetReplicaX`. The
presence of the suffix suggests there's a `non-X` version: but in fact
we migrated these away a long time ago, so remove the cognitive
overhead.

As an aside, this additionally helps avoid trip up LLMs that interpret
this as "something to fix".

server/channels/app/user_test.go

@@ -1116,7 +1116,7 @@ func TestPermanentDeleteUser(t *testing.T) {
 	bots2 := []*model.Bot{}
 
 	sqlStore := mainHelper.GetSQLStore()
-	err1 := sqlStore.GetMasterX().Select(&bots1, "SELECT * FROM Bots")
+	err1 := sqlStore.GetMaster().Select(&bots1, "SELECT * FROM Bots")
 	assert.NoError(t, err1)
 	assert.Equal(t, 1, len(bots1))
 
@@ -1127,7 +1127,7 @@ func TestPermanentDeleteUser(t *testing.T) {
 	err = th.App.PermanentDeleteUser(th.Context, retUser1)
 	assert.Nil(t, err)
 
-	err1 = sqlStore.GetMasterX().Select(&bots2, "SELECT * FROM Bots")
+	err1 = sqlStore.GetMaster().Select(&bots2, "SELECT * FROM Bots")
 	assert.NoError(t, err1)
 	assert.Equal(t, 0, len(bots2))