Bump Interpolations.jl compat to include 0.16

[thirtysixbananas]

Interpolations 0.16 has breaking changes. The one relevant here would be getindex with integer indices, but the tests pass.

https://github.com/JuliaMath/Interpolations.jl/releases/tag/v0.16.0

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.61%. Comparing base (d0b3f1f) to head (22156b7).
⚠️ Report is 15 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #44      +/-   ##
==========================================
+ Coverage   73.72%   75.61%   +1.89%     
==========================================
  Files           1        1              
  Lines         236      242       +6     
==========================================
+ Hits          174      183       +9     
+ Misses         62       59       -3     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.