Gemfile: pin rake version 10.1

rake 10.2.0 requires Ruby version >= 1.9.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4013001
add ChangeLog note that #15781 was forgotten to merge to v2.4.3.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4013004