add Flask logo

[Sameeratweb]

Adding Python-based framework - Flask's Logo
please allow me with this issue with relevant tags

[Eiim]

Same as #825: go for it!

[Smit1610]

@Sameeratweb can you please assign me this issue with hacktoberfest tag

[edent]

@Smit1610 please confirm you have read the contributing file?

[Smit1610]

yes @edent

[edent]

@Smit1610 Go for it! Remember to ask questions if you're not sure.