Bumping c7n to latest release

[jleopold28]

Description

• Bump c7n to release 0.9.4
• Bump c7n-mailer to release 0.6.3
• Updated dependencies for c7n and c7n-mailer

Contributor License Agreement

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[codecov-commenter]

Codecov Report

Merging #51 into master will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #51   +/-   ##
=======================================
  Coverage   57.61%   57.61%           
=======================================
  Files           8        8           
  Lines        1385     1385           
  Branches      261      261           
=======================================
  Hits          798      798           
  Misses        586      586           
  Partials        1        1           

Impacted Files	Coverage Δ
manheim_c7n_tools/version.py	100.00% <100.00%> (ø)

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