unittest: Convert EXPECT_EQ iterator checks to use EXPECT_TRUE instead

unittest: Convert EXPECT_EQ iterator checks to use EXPECT_TRUE instead

Hopefully fixes compile errors on some bots, like:

http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/13383/steps/ninja%20check%201/logs/stdio

/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/unittests/ADT/CoalescingBitVectorTest.cpp:452:3:   required from here
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/utils/unittest/googletest/include/gtest/gtest-printers.h:377:56: error: ‘const class llvm::CoalescingBitVector<long unsigned int>::const_iterator’ has no member named ‘begin’
   for (typename C::const_iterator it = container.begin();
                                                        ^
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/utils/unittest/googletest/include/gtest/gtest-printers.h:378:11: error: ‘const class llvm::CoalescingBitVector<long unsigned int>::const_iterator’ has no member named ‘end’
        it != container.end(); ++it, ++count) {
           ^