tests: add missing &&, batch 2

Same rules as before: this patch only adds " &&" to the end of
some lines in the test suite.

Intended to be applied on top of or squashed with the last
batch if they look okay.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>