build(deps): bump fluent-logger from 0.8.2 to 0.9.0

Bumps [fluent-logger](https://github.com/fluent/fluent-logger-ruby) from 0.8.2 to 0.9.0.
- [Release notes](https://github.com/fluent/fluent-logger-ruby/releases)
- [Changelog](https://github.com/fluent/fluent-logger-ruby/blob/master/ChangeLog)
- [Commits](fluent/fluent-logger-ruby@v0.8.2...v0.9.0)

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

Author: dependabot[bot]

Gemfile.lock

@@ -158,7 +158,7 @@ GEM
     ffi-compiler (1.0.1)
       ffi (>= 1.0.0)
       rake
-    fluent-logger (0.8.2)
+    fluent-logger (0.9.0)
       msgpack (>= 1.0.0, < 2)
     fog-aliyun (0.3.17)
       aliyun-sdk (~> 0.7.3)