Revert "REL-539: create 5.5.5 release notes" (#1599)

Reverts #1589

Author: oliverhowell

docs/modules/ROOT/nav.adoc

@@ -43,7 +43,6 @@
 ** xref:migrate:upgrading-from-imdg-3.adoc[]
 ** xref:migrate:migration-tool-imdg.adoc[]
 * xref:release-notes:releases.adoc[Release notes]
-** xref:release-notes:5-5-5.adoc[5.5.5]
 ** xref:release-notes:5-5-4.adoc[5.5.4]
 ** xref:release-notes:5-5-3.adoc[5.5.3]
 ** xref:release-notes:5-5-2.adoc[5.5.2]

docs/modules/release-notes/pages/5-5-5.adoc

@@ -2,7 +2,6 @@
 
 This section summarizes the changes in each release.
 
-* xref:release-notes:5-5-5.adoc[5.5.5]
 * xref:release-notes:5-5-4.adoc[5.5.4]
 * xref:release-notes:5-5-3.adoc[5.5.3]
 * xref:release-notes:5-5-2.adoc[5.5.2]