chore: remove circle ci (#4)

See https://github.com/libp2p/team-mgmt/issues/25

Circle CI was deprecate and @jacobheun agreed to remove it from all js repos.  This is the only non-JS repo where it still exists.  Requesting confirmation from @jacobheun or @daviddias that it's ok to delete this file.

circle.yml

@@ -1,12 +0,0 @@
-machine:
-  node:
-    version: stable
-
-dependencies:
-  pre:
-    - google-chrome --version
-    - wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -
-    - sudo sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google.list'
-    - sudo apt-get update
-    - sudo apt-get --only-upgrade install google-chrome-stable
-    - google-chrome --version