Fix stack trace comparison

[sgrekhov]

Fix

co19/blob/master/LanguageFeatures/Extension-types/dynamic_semantics_member_invocation_A02_t04
co19/blob/master/LanguageFeatures/Extension-types/dynamic_semantics_member_invocation_A03_t04

according to the dart-lang/sdk#53233 (comment)

[sgrekhov]

co19/LanguageFeatures/Extension-types/dynamic_semantics_member_invocation_A01_t02 must be fixed as well