Make IStore available via ISpecificationContext

[leonard84]

• Make IStore available via SpecificationContext
• Change IBlockListener to receive...

[leonard84]

Since #1575 hasn't been released yet, I'm only adding a release notes entry for the store part.

[AndreasTu]

LGTM.

[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 81.90%. Comparing base (2c7db77) to head (ca6ded6).
Report is 182 commits behind head on master.

Files with missing lines	Patch %	Lines
...ockframework/runtime/extension/IBlockListener.java	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2064      +/-   ##
============================================
+ Coverage     80.44%   81.90%   +1.45%     
- Complexity     4337     4688     +351     
============================================
  Files           441      452      +11     
  Lines         13534    14671    +1137     
  Branches       1707     1845     +138     
============================================
+ Hits          10888    12016    +1128     
+ Misses         2008     1975      -33     
- Partials        638      680      +42     

Files with missing lines	Coverage Δ
...java/org/spockframework/compiler/SpecRewriter.java	93.89% <100.00%> (+0.20%)	⬆️
...org/spockframework/runtime/PlatformSpecRunner.java	93.35% <100.00%> (-0.25%)	⬇️
...g/spockframework/runtime/SpecificationContext.java	100.00% <100.00%> (ø)
.../java/org/spockframework/runtime/SpockRuntime.java	84.18% <100.00%> (+4.05%)	⬆️
...java/org/spockframework/runtime/StoreProvider.java	100.00% <100.00%> (ø)
...ockframework/runtime/extension/IBlockListener.java	0.00% <0.00%> (ø)

... and 23 files with indirect coverage changes