Backport of Docs/reformat service splitters conf entry into release/1…

….15.x (#16283)

* backport of commit 99012ae

* backport of commit 0ffebd8

* backport of commit 352d079

* backport of commit 6b402e9

* backport of commit 9da4a1f

* backport of commit fabc679

* backport of commit b57075e

* backport of commit d3cc6ee

* Docs/reformat service splitters conf entry (#16264)

* for tab testing

* updates

* Update

* adding sandbox to test conf ref types

* testing tweaks to the conf ref template

* reintroduce tabbed specification

* applied feedback from MKO session

* applied feedback on format from luke and jared

* Apply suggestions from code review

Co-authored-by: Dan Upton <[email protected]>

* fixed some minor HCL formatting in complete conf

* Apply suggestions from code review

Co-authored-by: Jeff Boruszak <[email protected]>

* fixed bad link

* resolving conflicts

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Co-authored-by: boruszak <[email protected]>
Co-authored-by: Dan Upton <[email protected]>
Co-authored-by: Jeff Boruszak <[email protected]>

resolved cherry-pick conflicts

* trying to get rid of conflicts

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Co-authored-by: boruszak <[email protected]>
Co-authored-by: trujillo-adam <[email protected]>
Co-authored-by: trujillo-adam <[email protected]>