Fix tgz name and subfolder name mismatch (#169)

After extracting, checking the subdir for the tgz name is error prone.
If the tgz was renamed, for any reason, the update would fail.
This is easily noticeable with browser download:
duplicate downloads will have a (1) appended, causing a fail.
Choosing the first subdir of the tgz is sufficient.

backend/flipperzero/toplevel/fullupdateoperation.cpp

@@ -312,7 +312,7 @@ bool FullUpdateOperation::findAndCdToUpdateDir()
         const auto &fileInfo = it.fileInfo();
         const auto fileName = fileInfo.fileName();
 
-        if(fileInfo.isDir() && m_updateDirectory.dirName().endsWith(fileName)) {
+        if(fileInfo.isDir()) {
             m_updateDirectory.cd(fileName);
             return true;
         }