easy: Cleanup the go.mod/sum files (cadence-workflow#3275)

Some of the modules are not used anymore, run `go mod tidy` to perform a
quick cleanup.

go.mod

@@ -61,13 +61,11 @@ require (
 	go.opencensus.io v0.22.2 // indirect
 	go.uber.org/atomic v1.5.1
 	go.uber.org/cadence v0.11.3-0.20200408211929-2e8992a5ef2d
-	go.uber.org/fx v1.9.0
 	go.uber.org/multierr v1.3.0
 	go.uber.org/net/metrics v1.2.0 // indirect
 	go.uber.org/thriftrw v1.20.2
 	go.uber.org/yarpc v1.42.0
 	go.uber.org/zap v1.12.0
-	golang.org/x/net v0.0.0-20200114155413-6afb5195e5aa
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
 	golang.org/x/sys v0.0.0-20191029155521-f43be2a4598c // indirect
 	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4

go.sum

@@ -212,8 +212,10 @@ github.com/opentracing/opentracing-go v1.1.0/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFSt
 github.com/otiai10/copy v1.1.1 h1:PH7IFlRQ6Fv9vYmuXbDRLdgTHoP1w483kPNUP2bskpo=
 github.com/otiai10/copy v1.1.1/go.mod h1:rrF5dJ5F0t/EWSYODDu4j9/vEeYHMkc8jt0zJChqQWw=
 github.com/otiai10/curr v0.0.0-20150429015615-9b4961190c95/go.mod h1:9qAhocn7zKJG+0mI8eUu6xqkFDYS2kb2saOteoSB3cE=
+github.com/otiai10/curr v1.0.0 h1:TJIWdbX0B+kpNagQrjgq8bCMrbhiuX73M2XwgtDMoOI=
 github.com/otiai10/curr v1.0.0/go.mod h1:LskTG5wDwr8Rs+nNQ+1LlxRjAtTZZjtJW4rMXl6j4vs=
 github.com/otiai10/mint v1.3.0/go.mod h1:F5AjcsTsWUqX+Na9fpHb52P8pcRX2CI6A3ctIT91xUo=
+github.com/otiai10/mint v1.3.1 h1:BCmzIS3n71sGfHB5NMNDB3lHYPz8fWSkCAErHed//qc=
 github.com/otiai10/mint v1.3.1/go.mod h1:/yxELlJQ0ufhjUwhshSj+wFjZ78CnZ48/1wtmBH1OTc=
 github.com/pborman/uuid v0.0.0-20160209185913-a97ce2ca70fa/go.mod h1:VyrYX9gd7irzKovcSS6BIIEwPRkP2Wm2m9ufcdFSJ34=
 github.com/pborman/uuid v0.0.0-20180906182336-adf5a7427709 h1:zNBQb37RGLmJybyMcs983HfUfpkw9OTFD9tbBfAViHE=
@@ -425,6 +427,7 @@ golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8T
 gonum.org/v1/gonum v0.0.0-20180816165407-929014505bf4/go.mod h1:Y+Yx5eoAFn32cQvJDxZx5Dpnq+c3wtXuadVZAcxbbBo=
 gonum.org/v1/gonum v0.7.0 h1:Hdks0L0hgznZLG9nzXb8vZ0rRvqNvAcgAp84y7Mwkgw=
 gonum.org/v1/gonum v0.7.0/go.mod h1:L02bwd0sqlsvRv41G7wGWFCsVNZFv/k1xzGIxeANHGM=
+gonum.org/v1/netlib v0.0.0-20190313105609-8cb42192e0e0 h1:OE9mWmgKkjJyEmDAAtGMPjXu+YNeGvK9VTSHY6+Qihc=
 gonum.org/v1/netlib v0.0.0-20190313105609-8cb42192e0e0/go.mod h1:wa6Ws7BG/ESfp6dHfk7C6KdzKA7wR7u/rKwOGE66zvw=
 gonum.org/v1/plot v0.0.0-20190515093506-e2840ee46a6b/go.mod h1:Wt8AAjI+ypCyYX3nZBvf6cAIx93T+c/OS2HFAYskSZc=
 google.golang.org/api v0.4.0/go.mod h1:8k5glujaEP+g9n7WNsDg8QP6cUVNI86fCNMcbazEtwE=