pgAdmin 4 commit: Bump the version requirement for Flask-Gravatar to 0.

Bump the version requirement for Flask-Gravatar to 0.4.2.
This version has been restructured and plays nicely with our runtime.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=94bed721bd2f4157fa6629c197dd9e0a783cced6

Modified Files
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requirements_py2.txt            | 2 +-
requirements_py3.txt            | 2 +-
web/pgadmin/browser/__init__.py | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)