fix/test pgbinary crashing in single star mode

[Debraheem]

See gh-issue-634, this should fix a bug that crashed pgbinary when running in single-star mode with intel-based compilers. This did not affect my m1 machine.

The issue and fix were both found by @ryosuke-hirai and Sohan Ghodla so we should thank them for this.

To test this i made the star_plus_point_mass test_suite use the same pgstar controls as the evolve_both_stars test_suite to showcase pgbinary running in single star mode. I also changed the pgbinary flag to '.true.' so testing using the intel based compilers can catch if pgbinary produces a backtrace.

Once this is tested, and if the test_suite changes are allowed by @matthiasfabry and/or @orlox, I'll add this bug to the changelog and we can merge this.

[orlox]

@matthiasfabry is the pgbinary expert, so I'll leave this to him

[evbauer]

@matthiasfabry, this one should be ready to go. Can you take a quick look and merge if you think it's ready?

[matthiasfabry]

Thank you Ryosuke for this find! line 225 was fixed by @Debraheem, and I updated line 206. I will continue making improvements and adding features to pgbinary over the coming months. I would love to hear if you have suggestions or requests.