build(deps): bump fog-core from 2.1.2 to 2.2.4

Bumps [fog-core](https://github.com/fog/fog-core) from 2.1.2 to 2.2.4.
- [Release notes](https://github.com/fog/fog-core/releases)
- [Changelog](https://github.com/fog/fog-core/blob/master/changelog.md)
- [Commits](fog/fog-core@v2.1.2...v2.2.4)

---
updated-dependencies:
- dependency-name: fog-core
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Gemfile

@@ -62,7 +62,7 @@ gem 'fog-azure-rm', git: 'https://github.com/fog/fog-azure-rm.git', branch: 'fog
 gem 'fog-google', '~> 1.19.0'
 gem 'fog-local'
 gem 'fog-openstack'
-gem 'fog-core', '~> 2.1.2'
+gem 'fog-core', '~> 2.2.4'
 
 gem 'cf-uaa-lib', '~> 4.0.1'
 gem 'vcap-concurrency', git: 'https://github.com/cloudfoundry/vcap-concurrency.git', ref: '2a5b0179'

Gemfile.lock

@@ -168,9 +168,9 @@ GEM
       fog-core (~> 2.1)
       fog-json (~> 1.1)
       fog-xml (~> 0.1)
-    fog-core (2.1.2)
+    fog-core (2.2.4)
       builder
-      excon (~> 0.58)
+      excon (~> 0.71)
       formatador (~> 0.2)
       mime-types
     fog-google (1.19.0)
@@ -558,7 +558,7 @@ DEPENDENCIES
   fog-aliyun
   fog-aws
   fog-azure-rm!
-  fog-core (~> 2.1.2)
+  fog-core (~> 2.2.4)
   fog-google (~> 1.19.0)
   fog-local
   fog-openstack