Update TextModels for supporting flux-zygote

[tejasvaidhyadev]

Update TextAnalysis to Flux@0.10.0 with Zygote.

• Without compromising on performance, Zygote supports the full flexibility and dynamism of the Julia language, including control flow, recursion, closures, structs, dictionaries, and more.

• DiffEqFlux and NeuralNetDiffEq already moved to zygote.

• On the other hand Tracker is alive but is no longer heavily maintained so it is better to use Zygote