[DOCS] Add space to fix Asciidoctor output

[jrodewig]

Asciidoctor outputs ((MIN(salary) / 100)) as <indexterm><primary>MIN(salary) / 100</primary></indexterm>. This adds whitespace to correct the output in preparation for the Asciidoctor migration.

Relates to elastic/docs#827 and #41128.

[nik9000]

I know this is in the file called docs.csv-spec but I'm worried that folks will remove the spacing without realizing the change that it makes in the docs. I wonder if there is a better way to change this. Let me look around some!

[elasticmachine]

Pinging @elastic/es-docs

[nik9000]

This failure is caused because we use the macros substitution in this snippet which is required by AsciiDoc because include-tagged is a macro. But in Asciidoctor it isn't a macro. All include things are "special" and on regardless. So one way to fix this is:

+ifdef::asciidoctor[]
+[source,sql]
+endif::[]
+ifndef::asciidoctor[]
 ["source","sql",subs="attributes,callouts,macros"]
+endif::[]

This suggests that we probably should remove ,subs="attributes,callouts,macros" across the board once we migrate to asciidoctor as it is liable to cause trouble like these indexterms.

Now that I understand it I'm fine with either fix so long as we make sure to blast ,subs="attributes,callouts,macros" on the modern branches once we've migrated....

[jrodewig]

Thanks again, @nik9000! That asciidoctor conditional could be very handy.

I created #41589 to remove the subs="attributes,callouts,macros" options after Asciidoctor migration. That should keep us safe if that space is later removed.