fix eductional decoder

fix #1774
also :
- fix minor compilation warnings
- make sure the `test` is run during CI tests

lib/dictBuilder/cover.c

@@ -638,8 +638,8 @@ void COVER_warnOnSmallCorpus(size_t maxDictSize, size_t nbDmers, int displayLeve
                     "compared to the source size %u! "
                     "size(source)/size(dictionary) = %f, but it should be >= "
                     "10! This may lead to a subpar dictionary! We recommend "
-                    "training on sources at least 10x, and up to 100x the "
-                    "size of the dictionary!\n", (U32)maxDictSize,
+                    "training on sources at least 10x, and preferably 100x "
+                    "the size of the dictionary! \n", (U32)maxDictSize,
                     (U32)nbDmers, ratio);
 }