Merge pull request #1002 from libcpr/fix/openssl_include_ubuntu20_04

Fixed openssl/types.h include for ubuntu20.04

cpr/ssl_ctx.cpp

@@ -11,10 +11,19 @@
 #include <openssl/bio.h>
 #include <openssl/pem.h>
 #include <openssl/ssl.h>
-#include <openssl/types.h>
 #include <openssl/x509.h>
 #include <openssl/x509_vfy.h>
 
+// openssl/types.h was added in later version of openssl and is therefore not always available.
+// This is for example the case on Ubuntu 20.04.
+// We try to include it if available to satisfy clang-tidy.
+// Ref: https://github.com/openssl/openssl/commit/50cd4768c6b89c757645f28519236bb989216f8d
+#if __has_include(<openssl/types.h>)
+#include <openssl/types.h>
+#else
+#include <openssl/ossl_typ.h>
+#endif
+
 namespace cpr {
 
 /**