Fixes for building with `-pedantic`

Issues:

Relates to: aws/aws-lc-rs#425

Description of changes:

Fix compiler errors that occur when building the "crypto" & "ssl" targets with -pedantic.
Adds CI jobs gcc-14-pedantic and clang-18-pedantic.

Call-outs:

This only verifies that the "crypto" and "ssl" targets can be built. These are the two targets required by downstream packages, such as aws-lc-sys.

The -Wno-c99-c11-compat (GCC) and -Wno-c11-extensions (Clang) are to avoid a pedantic warning related to our use of _Generic:

/home/justsmth/repos/aws-lc/crypto/asn1/../internal.h:1099:4: error: ISO C99 does not support ‘_Generic’ [-Werror=pedantic]
1099 |   (_Generic((x),                                    \
  |    ^~~~~~~~

The -Wno-newline-eof is needed b/c Clang complains about a missing newline at the end of the s2n-bignum assembly files:

/home/justsmth/repos/aws-lc/third_party/s2n-bignum/include/_internal_s2n_bignum.h:17:7: warning: no newline at end of file [-Wnewline-eof]
17 | #endif
  |       ^

The -Wno-overlength-strings parameter was needed to avoid a failure due to string literals in err-data.c:

...
/tmp/tmp.SO3vhKEAo4/AWS-LC-BUILD/crypto/err_data.c:1603:5: error: string length ‘16178’ is greater than the length ‘4095’ ISO C99 compilers are required to support [-Werror=overlength-strings]
1603 |     "";
  |     ^~
...

Building our tests with -pedantic will still fail due largely to our tests using binary literals:

...
Files/crypto_test.dir/endian_test.cc.o -MF crypto/CMakeFiles/crypto_test.dir/endian_test.cc.o.d -o crypto/CMakeFiles/crypto_test.dir/endian_test.cc.o -c /home/justsmth/repos/aws-lc/crypto/endian_test.cc
/home/justsmth/repos/aws-lc/crypto/endian_test.cc:69:20: error: binary constants are a C++14 feature or GCC extension [-Werror]
69 |   uint32_t value = 0b00000010000000000000000000000;
  |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/justsmth/repos/aws-lc/crypto/endian_test.cc:70:23: error: binary constants are a C++14 feature or GCC extension [-Werror]
70 |   uint32_t expected = 0b00100000000000000000000000000;
  |                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/justsmth/repos/aws-lc/crypto/endian_test.cc:84:20: error: binary constants are a C++14 feature or GCC extension [-Werror]
84 |   uint64_t value = 0b0000001000000000000000000000000000010000000000000000000000;
  |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...

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aws / aws-lc