Improve ArchivesProviderTest

Ensure that all the Cursor and ContentProviderClient objects are
properly closed after use.

Ensure that all the "acquired" archives are properly "released".

Bug: 442716471
Bug: 435313862
Flag: EXEMPT fixing tests
Test: atest DocumentsUIGoogleTests:com.android.documentsui.ArchivesProviderTest
Change-Id: I2088b98124565e0d336706a6206e3a24b4b58f5d