test(app-check): cleanup quota exceeded handling

Skip cloud quota errors instead of asserting them, rethrow real failures,
and use CustomProvider on macOS where debug tokens are unavailable.

Author: mikehardy

.spellcheck.dict.txt

@@ -8,6 +8,7 @@ Analytics
 ANR
 APIs
 APIs.
+accessors
 APNs
 AppAttest
 AppCheck
@@ -221,6 +222,7 @@ src
 SSV
 stacktrace
 substring
+subpath
 switchOn
 SVG
 TestLab
@@ -258,6 +260,7 @@ v22
 v23
 v24
 v25
+v26
 Ventura
 VertexAI
 VPN