doc: fix a mistyped "=item" perldoc marker
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CLA: trivial
@@ -130,7 +130,7 @@ each of its sub-fields equals the corresponding subject key identifier, serial
number, and issuer field of the candidate issuer certificate,
as far as the respective fields are present in both certificates.
-item *
+=item *
The certificate signature algorithm used to sign the subject certificate
is supported and
