Revert "Exclude flow_analysis/data directories from analysis."

This reverts commit a003763.

Reason for revert: Paul already landed similar change.

Original change's description:
> Exclude flow_analysis/data directories from analysis.
> 
> Change-Id: I2bde938cf6fd14c65fdf281e4164c32884fff695
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/123760
> Reviewed-by: Johnni Winther <johnniwinther@google.com>
> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

TBR=paulberry@google.com,scheglov@google.com,johnniwinther@google.com

Change-Id: I244f3c3b16f6432d1957f971854525c04db41b8d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/123687
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

Author: scheglov

pkg/_fe_analyzer_shared/analysis_options_no_lints.yaml

@@ -3,12 +3,6 @@
 # BSD-style license that can be found in the LICENSE file.
 
 analyzer:
-  exclude:
-    - test/flow_analysis/assigned_variables/data/**
-    - test/flow_analysis/definite_assignment/data/**
-    - test/flow_analysis/nullability/data/**
-    - test/flow_analysis/reachability/data/**
-    - test/flow_analysis/type_promotion/data/**
   errors:
     # Allow having TODOs in the code
     todo: ignore