Fix issue where `enumNamespaces` rule wouldn't be applied following import statement

[calda]

This PR fixes an issue where the enumNamespaces rule wouldn't be applied to a type following an import statement. Fixes #1569.

[codecov[bot]]

Codecov Report

Merging #1576 (a9f875e) into develop (a22fbc3) will decrease coverage by 0.05%. The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop    #1576      +/-   ##
===========================================
- Coverage    95.03%   94.99%   -0.05%     
===========================================
  Files           20       20              
  Lines        21842    21841       -1     
===========================================
- Hits         20757    20747      -10     
- Misses        1085     1094       +9     

Files	Coverage Δ
Sources/Rules.swift	98.53% <100.00%> (-0.01%)	:arrow_down:

... and 5 files with indirect coverage changes

[nicklockwood]

Thank you!