Description

Path provider currently depends on the full guava package, which causes build issues like this:

> 1 exception was raised by workers:
  java.lang.RuntimeException: Duplicate class com.google.common.util.concurrent.ListenableFuture found in modules guava-20.0.jar (com.google.guava:guava:20.0) and listenablefuture-1.0.jar (com.google.guava:listenablefuture:1.0)
  Go to the documentation to learn how to <a href="d.android.com/r/tools/classpath-sync-errors">Fix dependency resolution errors</a>.
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 6m 15s

This PR adjusts this back to guava-android.

Without it, projects that depend on work manager for example, will break.

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
• The analyzer (flutter analyze) does not report any problems on my PR.
• I read and followed the Flutter Style Guide.
• The title of the PR starts with the name of the plugin surrounded by square brackets, e.g. [shared_preferences]
• I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy.
• I updated CHANGELOG.md to add a description of the change.
• I signed the CLA.
• I am willing to follow-up on review comments in a timely manner.

Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• Yes, this is a breaking change (please indicate a breaking change in CHANGELOG.md and increment major revision).
• No, this is not a breaking change.