[breaking] rename SymMatrixSpace to SymmetricMatrixSpace

[odow]

Part of #2884

cc @ccoffrin

[codecov]

Codecov Report

Merging #2889 (19ed82b) into master (e7ffb7c) will decrease coverage by 0.03%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master    #2889      +/-   ##
==========================================
- Coverage   95.27%   95.23%   -0.04%     
==========================================
  Files          43       43              
  Lines        5688     5690       +2     
==========================================
  Hits         5419     5419              
- Misses        269      271       +2     

Impacted Files	Coverage Δ
src/sd.jl	91.66% <33.33%> (-1.96%)	⬇️
src/macros.jl	95.65% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update e7ffb7c...19ed82b. Read the comment docs.