Bump github.com/google/go-cmp from 0.5.1 to 0.5.2 in /propagators (#346)

Bumps [github.com/google/go-cmp](https://github.com/google/go-cmp) from 0.5.1 to 0.5.2.
- [Release notes](https://github.com/google/go-cmp/releases)
- [Commits](google/go-cmp@v0.5.1...v0.5.2)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

propagators/go.mod

@@ -5,7 +5,7 @@ go 1.14
 replace go.opentelemetry.io/contrib => ./..
 
 require (
-	github.com/google/go-cmp v0.5.1
+	github.com/google/go-cmp v0.5.2
 	github.com/stretchr/testify v1.6.1
 	go.opentelemetry.io/contrib v0.11.0
 	go.opentelemetry.io/otel v0.11.0

propagators/go.sum

@@ -4,6 +4,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.5.1 h1:JFrFEBb2xKufg6XkJsJr+WbKb4FQlURi5RUcBveYu9k=
 github.com/google/go-cmp v0.5.1/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.2 h1:X2ev0eStA3AbceY54o37/0PQ/UWqKEiiO2dKL5OPaFM=
+github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=