slaprunner and seleniumserver: Use ecdsa SSH keys in tests

After upgrade to OpensSSH 8.8p1 the simple ssh-rsa keys are not accepted
anymore.

software/seleniumserver/test/test.py

@@ -337,8 +337,8 @@ class TestFrontend(WebServerMixin, SeleniumServerTestCase):
 class TestSSHServer(SeleniumServerTestCase):
   @classmethod
   def getInstanceParameterDict(cls):
-    cls.ssh_key = paramiko.RSAKey.generate(1024)
-    return {'ssh-authorized-key': 'ssh-rsa {}'.format(cls.ssh_key.get_base64())}
+    cls.ssh_key = paramiko.ECDSAKey.generate(bits=384)
+    return {'ssh-authorized-key': 'ecdsa-sha2-nistp384 {}'.format(cls.ssh_key.get_base64())}
 
   def test_connect(self):
     parameter_dict = self.computer_partition.getConnectionParameterDict()

software/slaprunner/test/test.py

@@ -339,9 +339,9 @@ class TestWeb(SlaprunnerTestCase):
 class TestSSH(SlaprunnerTestCase):
   @classmethod
   def getInstanceParameterDict(cls):
-    cls.ssh_key_list = [paramiko.RSAKey.generate(1024) for i in range(2)]
+    cls.ssh_key_list = [paramiko.ECDSAKey.generate(bits=384) for i in range(2)]
     return {
-        'user-authorized-key': 'ssh-rsa {}\nssh-rsa {}'.format(
+        'user-authorized-key': 'ecdsa-sha2-nistp384 {}\necdsa-sha2-nistp384 {}'.format(
           *[key.get_base64() for key in cls.ssh_key_list]
           )
     }
@@ -363,7 +363,7 @@ class TestSSH(SlaprunnerTestCase):
     username, fingerprint_from_url = ssh_info.split(';fingerprint=')
     client = paramiko.SSHClient()
 
-    self.assertTrue(fingerprint_from_url.startswith('ssh-rsa-'), '')
+    self.assertTrue(fingerprint_from_url.startswith('ssh-rsa-'), fingerprint_from_url)
     fingerprint_from_url = fingerprint_from_url[len('ssh-rsa-'):]
 
     class KeyPolicy(object):