fix: only put 'empty_print_endl' at the end of 'print' arguments

[gxyd]

Fixes #3850

[gxyd]

I'm curious, for why the current PRINT node in ASR is:

Print(expr* values, expr? separator, expr? end)

and AST node is:

Print(int label, expr? fmt, expr* values, trivia? trivia)

while in the J3 documentation, it has only "format" (which was removed here: #2471).

I'm curious for how would a user specify a "separator" and "end" for an ASR node? @certik @Thirumalai-Shaktivel?

[gxyd]

I'm keeping this PR in "open" as I'm looking for the answer to the above questions, and I'm not ready to get this merged before I understand the purpose of having separator and end for how would a user actually specify them in Fortran.

[certik]

See this comment: #2471 (comment), I think the ASR node for print should just accept a string, that's it. All formatting should be done using the StringFormat node.

In StringFormat node, you can add a separator in a few different ways.