Adds hypot math function

[auto-differentiation-dev]

Description

This adds the standard math function hypot (introduced in C++11), which allows calculating
sqrt(x*x + y*y) without potential overflow for intermediate results.

This function is then used in complex abs, fixing an issue when infinity was returned for
large numbers.

Type of change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)

[coveralls]

coverage: 98.56% (+0.005%) from 98.555%
when pulling 70ff612 on feature/hypot-function
into 415838a on main.

[github-actions]

Test Results

    29 files  ±  0      29 suites  ±0   12m 6s ⏱️ +17s
 1 271 tests +  5   1 271 ✅ +  5  0 💤 ±0  0 ❌ ±0 
36 859 runs  +145  36 859 ✅ +145  0 💤 ±0  0 ❌ ±0 

Results for commit 70ff612. ± Comparison against base commit 415838a.

♻️ This comment has been updated with latest results.