Ruby AST specs: Make description of context-checking tests more generic
Ruby AST specs: Make description of context-checking tests more generic

This commit changes test descriptions like

  it "passes correct available space info to #to_ruby"

to

  it "passes correct context to #to_ruby"

This is because these tests may also check other things beside space
info in passed contexts in the future. The new way is also a bit
shorter.

yast/y2r