github.com: Invalid certificate

On Running Example got error,

```
I/flutter (19203): GitRepo Initialized
I/GitJournalAndroid(19203): Called method generateSSHKeys
I/GitJournalAndroid(19203): . comment: Git Sample App
D/GenerateSSHKeys(19203): Private key already exists. Overwriting
I/GitJournalAndroid(19203): Called method gitClone
I/GitJournalAndroid(19203): . folderPath: /data/user/0/com.example.git_bindings_example/files/journal
I/GitJournalAndroid(19203): . cloneUrl: git@github.com:GitJournal/journal_test.git
W/com.example.git_bindings_example(19203): type=1400 audit(0.0:238901): avc: denied { link } for comm=4173796E635461736B202331 name="HEAD.lock" dev="sda31" ino=2104527 scontext=u:r:untrusted_app_27:s0:c196,c258,c512,c768 tcontext=u:object_r:app_data_file:s0:c196,c258,c512,c768 tclass=file permissive=0
E/GitJournalLib(19203): Valid: 0
E/GitJournalLib(19203): CertType: 2
E/GitJournalLib(19203): github.com: Invalid certificate
E/GitJournalLib(19203): LibSSH2 Key: 0x78cff3b3c8
E/GitJournalLib(19203): Url: git@github.com:GitJournal/journal_test.git
E/GitJournalLib(19203): GitJournal: Credentials have been tried and they failed
E/GitJournalLib(19203): gj_error_info: -957
E/GitJournalLib(19203): Error -957/-957: Invalid Credentials
I/flutter (19203): GitException: Invalid Credentials
```