Fix NetworkSecurityConfigTest tests

Update the intermediate certificate pin reference (WR2).

Other tests were failing because HttpsURLConnection was trying to follow
the HTTP 301 returned by android.com to www.android.com. Update
TestUtils to not follow any HTTP redirection.

Test: atest NetworkSecurityConfigTest
Bug: 259406200
Change-Id: I570b12b1d665270aeddb38379f4bc10abbe674e6