AMS template.tex: Fix brace in author2

[ConorIA]

As written, the authors block is never closed when there is no \currentaddress for author 2. I've also moved the closing $endif$ for $if(author1)$ so that we don't end up with a stray brace when no authors are specified.

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[cderv]

Thanks !

This looks ok to me.

IMO, this part could be rewriten to use a for loop for authors like in other template. For example:

rticles/inst/rmarkdown/templates/arxiv/resources/template.tex

Lines 17 to 31 in 6088e66

	\author{
	$for(authors)$
	$authors.name$
	$if(authors.thanks)$
	\thanks{$authors.thanks$}
	$endif$ \\
	$if(authors.department)$
	$authors.department$ \\
	$endif$
	$authors.affiliation$ \\
	$authors.location$ \\
	\texttt{$authors.email$} \\
	$sep$ \And
	$endfor$
	}

Currently, there could only be two authors for example. But maybe that is required by the template, IDK.

ping @yufree as you are the one submitted this template in the first place. FYI.

[cderv]

Thank you @ConorIA !

[yufree]

Thanks for PR!
author1 is for the old AMS latex template to deal with two authors situation. As mentioned in #298 , AMS has released v5 template which will no longer need author1. However, to make the rticle AMS template work, such change is necessary. In long term, rticle AMS template will shift to new version.

[cderv]

Great ! I forgot about his PR!