fix: removed pkg otel-api because imported twice (#860)

I doubt it's the cause of any trouble but I saw that otel-api is
importend twice in package.json

Signed-off-by: Gianluca Arbezzano <[email protected]>

Author: gianarb

examples/redis/package.json

@@ -37,7 +37,6 @@
     "@opentelemetry/plugin-http": "^0.4.0",
     "@opentelemetry/plugin-redis": "^0.4.0",
     "@opentelemetry/tracing": "^0.4.0",
-    "@opentelemetry/api": "^0.4.0",
     "axios": "^0.19.0",
     "express": "^4.17.1",
     "redis": "^2.8.0"