Unify expectations writing #1778 (#1833)

* Unify expectations writing #1778

* Update video-only-as-media-alternative-fd26cf.md

* Update video-as-media-alternative-ab4d13.md

* Update audio-as-media-alternative-afb423.md

* Update _rules/audio-as-media-alternative-afb423.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

* Update video-as-media-alternative-ab4d13.md

* Update video-only-as-media-alternative-fd26cf.md

* Update _rules/audio-as-media-alternative-afb423.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

* Update _rules/audio-as-media-alternative-afb423.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

* Update _rules/video-only-as-media-alternative-fd26cf.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

* Update _rules/video-as-media-alternative-ab4d13.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

* Update audio-as-media-alternative-afb423.md

* Update video-as-media-alternative-ab4d13.md

* Update video-only-as-media-alternative-fd26cf.md

Co-authored-by: Jean-Yves Moyen <jym@siteimprove.com>

Author: HelenBurge

_rules/audio-as-media-alternative-afb423.md

@@ -33,9 +33,8 @@ The auditory information of each test target is available as text (directly or v
 
 ## Expectation 2
 
-Each target element is labeled as an audio alternative for text on the page. This label is [visible][] and [included in the accessibility tree][].
+Each target element is labeled as an audio alternative for text on the page by content that is [visible][] and [included in the accessibility tree][].
 
-**Note:** The term label does not refer to the `label` element.
 
 ## Assumptions
 

_rules/video-as-media-alternative-ab4d13.md

@@ -30,9 +30,8 @@ All the information contained in each test target is available as text that is [
 
 ## Expectation 2
 
-Each test target is labeled as a video alternative for text on the page. This label is [visible][] and [included in the accessibility tree][].
+Each target element is labeled as a video alternative for text on the page by content that is [visible][] and [included in the accessibility tree][].
 
-**Note:** The term label does not refer to the `label` element.
 
 ## Assumptions
 

_rules/video-only-as-media-alternative-fd26cf.md

@@ -30,11 +30,8 @@ All the information contained in each target element is available as text (direc
 
 ## Expectation 2
 
-Each target element is labeled as a video alternative for text on the page.
+Each target element is labeled as a video alternative for text on the page by content that is [visible][] and [included in the accessibility tree][].
 
-## Expectation 3
-
-The label (from expectation 2) is [visible][] and [included in the accessibility tree][].
 
 ## Assumptions