RemoteInspection: Add AsyncTaskInfo.IsSuspended based on HasTaskDependency

[kastiglione]

Adds an IsSuspended field to AsyncTaskInfo, which is the same value as HasTaskDependency, but uses the Is<State> naming to match IsEnqueued, IsRunning, and IsComplete.

Based on the docs in Task.h:

/// A task can have the following states:
///   * suspended: In this state, a task is considered not runnable
///   * enqueued: In this state, a task is considered runnable
///   * running on a thread
///   * completed

rdar://148663671

[kastiglione]

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