user-docs: remove index-attestations preview feature (#19162)

Signed-off-by: William Woodruff <[email protected]>
Co-authored-by: Mike Fiedler <[email protected]>

Author: woodruffw

docs/user/attestations/consuming-attestations.md

@@ -1,7 +1,5 @@
 # Consuming attestations
 
-<!--[[ preview('index-attestations') ]]-->
-
 PyPI makes a file's attestations available via the simple index (HTML)
 and simple JSON APIs.
 
@@ -12,7 +10,7 @@ For a full API reference, see the [Integrity API documentation].
 Since a distribution file can have multiple attestations, and PyPI serves
 these attestations as a single JSON file, this JSON file groups the
 attestations into a single [provenance object]. This object contains
-bundles of attestations grouped by the Trusted Publisher identity used 
+bundles of attestations grouped by the Trusted Publisher identity used
 to sign them.
 
 To manually verify a PyPI artifact against its provenance object,

docs/user/attestations/index.md

@@ -2,8 +2,6 @@
 title: Introduction
 ---
 
-<!--[[ preview('index-attestations') ]]-->
-
 These pages document PyPI's implementation of digital attestations ([PEP 740]),
 including in-toto attestation predicates specific to PyPI itself.
 

docs/user/attestations/producing-attestations.md

@@ -1,7 +1,5 @@
 # Producing attestations
 
-<!--[[ preview('index-attestations') ]]-->
-
 PyPI allows attestations to be attached to individual *release files*
 (source and binary distributions within a release) at upload time.
 

docs/user/attestations/publish/v1.md

@@ -2,8 +2,6 @@
 title: PyPI Publish Attestation (v1)
 ---
 
-<!--[[ preview('index-attestations') ]]-->
-
 Type URI: <https://docs.pypi.org/attestations/publish/v1>
 
 Version 1.0

docs/user/main.py

@@ -1,15 +1,6 @@
 from pathlib import Path
 
-INDEX_ATTESTATIONS = """
-!!! info
-
-    Index attestations are currently under active development,
-    and are not yet considered stable.
-"""
-
-PREVIEW_FEATURES = {
-    "index-attestations": INDEX_ATTESTATIONS,
-}
+PREVIEW_FEATURES = {}
 
 _HERE = Path(__file__).parent.resolve()