Use spdlog_setup::spdlog_setup as the target in CMake config

[jakecobb]

Fixes Issue #21

[codecov]

Codecov Report

Merging #22 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #22   +/-   ##
=======================================
  Coverage   88.01%   88.01%           
=======================================
  Files           3        3           
  Lines         409      409           
=======================================
  Hits          360      360           
  Misses         49       49

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[guangie88]

Thanks for catching this bug! 👍 Noted the namespace prepended when exporting spdlog_setup into spdlog_setup-targets.cmake.