[space-age] Add a Jinja test template

[IsaacG]

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[colinleach]

Fixing the compiler error just needs a d0 added to the expected value, but now we have a precision issue. The old test file specifies expected to 17 decimal places, `problem-specifications rounds to 2 decimal places.

• The ultra-precise calculation is kind of in the spirit of Fortran.
• Canonical data for this exercise is pretty stable, so we don't need to keep re-syncing.

I'm tempted to leave it as-is, but I'd welcome your opinion.

[IsaacG]

If the precision is idiomatic Fortran, we could totally keep it in. I'm not remotely familiar with what is and isn't idiomatic here. We could probably re-implement the solution in the Jinja template file and have three template spit out expected value to 17 decimal places. Feel free to take a crack at that or I can try to circle back to this later.