[libc] Add -Werror for libc tests

[vinay-deshmukh]

Relates to #119281

[github-actions]

⚠️ C/C++ code formatter, clang-format found issues in your code. ⚠️

You can test this locally with the following command:

git-clang-format --diff origin/main HEAD --extensions cpp -- libc/test/include/complex_test.cpp libc/test/src/math/exhaustive/bfloat16_add_test.cpp libc/test/src/math/exhaustive/bfloat16_div_test.cpp libc/test/src/math/exhaustive/bfloat16_mul_test.cpp libc/test/src/math/exhaustive/bfloat16_sub_test.cpp libc/test/src/signal/sigaltstack_test.cpp libc/test/src/stdio/fileop_test.cpp libc/test/src/stdio/fopen_test.cpp libc/test/src/sys/socket/linux/send_recv_test.cpp libc/test/src/sys/socket/linux/sendmsg_recvmsg_test.cpp libc/test/src/sys/socket/linux/sendto_recvfrom_test.cpp libc/test/src/time/ctime_r_test.cpp libc/test/src/time/mktime_test.cpp

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View the diff from clang-format here.

diff --git a/libc/test/src/time/mktime_test.cpp b/libc/test/src/time/mktime_test.cpp
index 77ddc326b..8d93165e8 100644
--- a/libc/test/src/time/mktime_test.cpp
+++ b/libc/test/src/time/mktime_test.cpp
@@ -644,8 +644,7 @@ TEST(LlvmLibcMkTime, Max64BitYear) {
                       .tm_wday = 0,
                       .tm_yday = 0,
                       .tm_isdst = 0};
-    EXPECT_THAT(LIBC_NAMESPACE::mktime(&tm_data),
-                Succeeds(67767976202043050));
+    EXPECT_THAT(LIBC_NAMESPACE::mktime(&tm_data), Succeeds(67767976202043050));
     EXPECT_TM_EQ((tm{.tm_sec = 50,
                      .tm_min = 50,
                      .tm_hour = 12,