Fixed failing tests of AutoCompleteTextView for lower android versions.

[aditya-07]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes #970

Description
After analyzing the trace, Added @UiThreadTest to the setup for tests where the Layout was getting inflated.

Alternative(s) considered
Have you considered any alternatives? And if so, why have you chosen the approach in this PR?

Type
Choose one: Bug fix

Screenshots (if applicable)

Checklist

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• I have discussed my proposed solution with code owners in the linked issue(s) and we have agreed upon the general approach
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[codecov]

Codecov Report

Merging #972 (d96ddd2) into master (43ccab2) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #972   +/-   ##
=========================================
  Coverage     88.27%   88.27%           
  Complexity      500      500           
=========================================
  Files           113      113           
  Lines          9390     9390           
  Branches        654      654           
=========================================
  Hits           8289     8289           
  Misses          751      751           
  Partials        350      350           

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