Removed missing Ubuntu 18 checksum

Author: rrelledge

content/operate/rs/release-notes/rs-7-2-4-releases/rs-7-2-4-130.md

@@ -87,7 +87,6 @@ The following table shows the MD5 checksums for the available packages:
 
 | Package | MD5 checksum (7.2.4-130 May release) |
 |---------|---------------------------------------|
-| Ubuntu 18 |  |
 | Ubuntu 20 | 121004b2795ed37d8cb97c4bc6bbbe2b |
 | Red Hat Enterprise Linux (RHEL) 7 | b9fcb3b7611cbfa33ae79f6cfff4ac1b |
 | Red Hat Enterprise Linux (RHEL) 8 | e61d9bcac8dbde4ca4ef69d5621c31e6 |