Bump go.opentelemetry.io/otel (open-telemetry#146)

Bumps [go.opentelemetry.io/otel](https://github.com/open-telemetry/opentelemetry-go) from 0.17.0 to 0.18.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-go/releases)
- [Changelog](https://github.com/open-telemetry/opentelemetry-go/blob/main/CHANGELOG.md)
- [Commits](open-telemetry/opentelemetry-go@v0.17.0...v0.18.0)

Signed-off-by: dependabot[bot] <[email protected]>

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

examples/prometheus-federation/prom-counter/go.mod

@@ -3,8 +3,8 @@ module app
 go 1.14
 
 require (
-	go.opentelemetry.io/otel v0.17.0
+	go.opentelemetry.io/otel v0.18.0
 	go.opentelemetry.io/otel/exporters/metric/prometheus v0.17.0
-	go.opentelemetry.io/otel/metric v0.17.0
+	go.opentelemetry.io/otel/metric v0.18.0
 	go.uber.org/zap v1.16.0
 )

examples/prometheus-federation/prom-counter/go.sum

@@ -279,12 +279,18 @@ go.opencensus.io v0.20.2/go.mod h1:6WKK9ahsWS3RSO+PY9ZHZUfv2irvY6gN279GOPZjmmk=
 go.opencensus.io v0.22.2/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opentelemetry.io/otel v0.17.0 h1:6MKOu8WY4hmfpQ4oQn34u6rYhnf2sWf1LXYO/UFm71U=
 go.opentelemetry.io/otel v0.17.0/go.mod h1:Oqtdxmf7UtEvL037ohlgnaYa1h7GtMh0NcSd9eqkC9s=
+go.opentelemetry.io/otel v0.18.0 h1:d5Of7+Zw4ANFOJB+TIn2K3QWsgS2Ht7OU9DqZHI6qu8=
+go.opentelemetry.io/otel v0.18.0/go.mod h1:PT5zQj4lTsR1YeARt8YNKcFb88/c2IKoSABK9mX0r78=
 go.opentelemetry.io/otel/exporters/metric/prometheus v0.17.0 h1:36x/2SxZqIx0f/T5+nEwKHMPd3pKTJvP7JvdWD2E1hw=
 go.opentelemetry.io/otel/exporters/metric/prometheus v0.17.0/go.mod h1:FpM7K2k0TgHMzrsRM5UFCxJzOJqu1Vitcv8bUc7xZXg=
 go.opentelemetry.io/otel/metric v0.17.0 h1:t+5EioN8YFXQ2EH+1j6FHCKMUj+57zIDSnSGr/mWuug=
 go.opentelemetry.io/otel/metric v0.17.0/go.mod h1:hUz9lH1rNXyEwWAhIWCMFWKhYtpASgSnObJFnU26dJ0=
+go.opentelemetry.io/otel/metric v0.18.0 h1:yuZCmY9e1ZTaMlZXLrrbAPmYW6tW1A5ozOZeOYGaTaY=
+go.opentelemetry.io/otel/metric v0.18.0/go.mod h1:kEH2QtzAyBy3xDVQfGZKIcok4ZZFvd5xyKPfPcuK6pE=
 go.opentelemetry.io/otel/oteltest v0.17.0 h1:TyAihUowTDLqb4+m5ePAsR71xPJaTBJl4KDArIdi9k4=
 go.opentelemetry.io/otel/oteltest v0.17.0/go.mod h1:JT/LGFxPwpN+nlsTiinSYjdIx3hZIGqHCpChcIZmdoE=
+go.opentelemetry.io/otel/oteltest v0.18.0 h1:FbKDFm/LnQDOHuGjED+fy3s5YMVg0z019GJ9Er66hYo=
+go.opentelemetry.io/otel/oteltest v0.18.0/go.mod h1:NyierCU3/G8DLTva7KRzGii2fdxdR89zXKH1bNWY7Bo=
 go.opentelemetry.io/otel/sdk v0.17.0 h1:eHXQwanmbtSHM/GcJYbJ8FyyH/sT9a0e+1Z9ZWkF7Ug=
 go.opentelemetry.io/otel/sdk v0.17.0/go.mod h1:INs1PePjjF2hf842AXsxGTe5lH023QfLTZRFPiV/RUk=
 go.opentelemetry.io/otel/sdk/export/metric v0.17.0 h1:RKOa26LDq4JBRwUnWwY64ccc27v1rA20z0q71aq4WFs=
@@ -293,6 +299,8 @@ go.opentelemetry.io/otel/sdk/metric v0.17.0 h1:l9W/OcHwyq3ZPqk4V6OS5ED50z9A6yI8N
 go.opentelemetry.io/otel/sdk/metric v0.17.0/go.mod h1:zAX55SrmDMpZwfQrz1PKIPbCP5beU+JPQTfNko01deo=
 go.opentelemetry.io/otel/trace v0.17.0 h1:SBOj64/GAOyWzs5F680yW1ITIfJkm6cJWL2YAvuL9xY=
 go.opentelemetry.io/otel/trace v0.17.0/go.mod h1:bIujpqg6ZL6xUTubIUgziI1jSaUPthmabA/ygf/6Cfg=
+go.opentelemetry.io/otel/trace v0.18.0 h1:ilCfc/fptVKaDMK1vWk0elxpolurJbEgey9J6g6s+wk=
+go.opentelemetry.io/otel/trace v0.18.0/go.mod h1:FzdUu3BPwZSZebfQ1vl5/tAa8LyMLXSJN57AXIt/iDk=
 go.uber.org/atomic v1.3.2/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.5.0/go.mod h1:sABNBOSYdrvTF6hTgEIbc7YasKWGhgEQZyfxyTvoXHQ=
 go.uber.org/atomic v1.6.0 h1:Ezj3JGmsOnG1MoRWQkPBsKLe9DwWD9QeXzTRzzldNVk=