fix: app crash in playstore version on signup

Fixes: #1531

Changes:

- Replace lateinit variables with null initialised variables to fix crash

Author: addiegupta

app/src/playStore/java/org/fossasia/openevent/general/search/SmartAuthViewModel.kt

@@ -23,9 +23,9 @@ const val RC_CREDENTIALS_SAVE = 3
 
 class SmartAuthViewModel : ViewModel() {
     private var requestedCredentialsEarlier = false
-    private lateinit var credentialsClient: CredentialsClient
-    private lateinit var signInClient: GoogleSignInClient
-    private lateinit var thisActivity: Activity
+    private var credentialsClient: CredentialsClient? = null
+    private var signInClient: GoogleSignInClient? = null
+    private var thisActivity: Activity? = null
     private val mutableId = MutableLiveData<String>()
     val id: LiveData<String> = mutableId
     private val mutablePassword = MutableLiveData<String>()
@@ -51,7 +51,7 @@ class SmartAuthViewModel : ViewModel() {
             .setPasswordLoginSupported(true)
         crBuilder.setAccountTypes(IdentityProviders.GOOGLE)
         mutableProgress.value = true
-        credentialsClient.request(crBuilder.build()).addOnCompleteListener(
+        credentialsClient?.request(crBuilder.build())?.addOnCompleteListener(
             OnCompleteListener<CredentialRequestResponse> { task ->
                 requestedCredentialsEarlier = true
 
@@ -73,7 +73,7 @@ class SmartAuthViewModel : ViewModel() {
     fun saveCredential (activity: Activity?, id: String, password: String) {
         if (activity == null) return
         val credential = Credential.Builder(id).setPassword(password).build()
-        credentialsClient.save(credential).addOnCompleteListener(
+        credentialsClient?.save(credential)?.addOnCompleteListener(
             OnCompleteListener<Void> { task ->
                 if (task.isSuccessful)
                     return@OnCompleteListener