Follow-up to MDEV-13227: Do not run unnecessary test combinations

The bug only affected innodb_page_size=64k. There is no point
running the test with smaller page sizes.

mysql-test/suite/innodb/t/innodb-enlarge-blob.opt

 --innodb-file-per-table
 --innodb-file-format='Barracuda'
 --innodb-buffer-pool-size=32M
---innodb-log-file-size=32M
+--innodb-page-size=64k
 --innodb-strict-mode=OFF
-

mysql-test/suite/innodb/t/innodb-enlarge-blob.test

 --source include/have_innodb.inc
---source include/innodb_page_size.inc
 
 #
 # MDEV-13227: Assertion failure len < 16384 in file rem0rec.cc line 1285