RFR (XS) 8231859 : Extra dash after the exception name in @throws clause of javadoc

[Ivan Gerasimov]

Hello!

This is a javadoc-only cleanup.

In a few places a dash was used between the exception name and the 
description under the @throws tag.

This causes a double dash in the produced documentation.  For example, 
see 
https://docs.oracle.com/en/java/javase/12/docs/api/java.base/java/security/PermissionCollection.html#add(java.security.Permission)

Would you please help review a trivial cleanup?

BUGURL: https://bugs.openjdk.java.net/browse/JDK-8231859
WEBREV: http://cr.openjdk.java.net/~igerasim/8231859/00/webrev/

-- 
With kind regards,
Ivan Gerasimov