Fix extraDirectories filtering to match relative path

[chanseokoh]

Most of the time, you'll specify a relative path in <includes> and <excludes>, which is the case in all of our tests.

Turns out we need to relativize local path to match against the glob matchers. The reason the tests seemed to work was that we always started with **/, which works for absolute path. That is, previously, includes = ['foo'] didn't work.

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Previous PR: #3173
Issues: #2564 #3164

[codecov]

Codecov Report

Merging #3181 (0098c29) into master (6a415b8) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##             master    #3181   +/-   ##
=========================================
  Coverage     71.18%   71.19%           
  Complexity     2331     2331           
=========================================
  Files           279      279           
  Lines          9846     9848    +2     
  Branches        990      990           
=========================================
+ Hits           7009     7011    +2     
  Misses         2491     2491           
  Partials        346      346           

Impacted Files	Coverage Δ	Complexity Δ
...jib/plugins/common/JavaContainerBuilderHelper.java	95.45% <100.00%> (+0.14%)	21.00 <3.00> (ø)

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[mpeddada1]

LGTM