Fix boot VTS GetSuffix test

Rather than requiring "_a" and "_b" specifically, check format and
uniqueness of each suffix.

Bug: 69795155
Test: vts-tradefed run vts -m VtsHalBootV1_0Target
Change-Id: Iaf626a31b499ef74fd3c21b0a0757424a0def457
Signed-off-by: Connor O'Brien <[email protected]>
1 file changed