Refactor session initialization checks and clean up unused methods

- Updated the order of conditions in expectDelayedSessionInitialization for clarity.
- Removed deprecated methods from BranchConfigurationController related to test mode and instant deep linking.
- Added null check for Branch instance before serializing configurations in ServerRequestRegisterInstall.

Author: wpinho-branch

Branch-SDK/src/main/java/io/branch/referral/Branch.java

@@ -511,7 +511,7 @@ public void disableAdNetworkCallouts(boolean disabled) {
      */
     public static void expectDelayedSessionInitialization(boolean expectDelayedInit) {
         disableAutoSessionInitialization = expectDelayedInit;
-        if (expectDelayedInit && Branch.getInstance() != null) {
+        if (Branch.getInstance() != null && expectDelayedInit) {
             Branch.getInstance().branchConfigurationController_.setDelayedSessionInitUsed(true);
         }
     }

Branch-SDK/src/main/java/io/branch/referral/BranchConfigurationController.kt

@@ -33,18 +33,6 @@ class BranchConfigurationController {
         return Branch.getInstance().prefHelper_.delayedSessionInitUsed
     }
 
-    /**
-     * Sets whether test mode is enabled.
-     * This flag is used to track if the app is running in test mode.
-     */
-    fun setTestModeEnabled(enabled: Boolean) {
-        if (enabled) {
-            Branch.enableTestMode()
-        } else {
-            Branch.disableTestMode()
-        }
-    }
-
     /**
      * Gets whether test mode is enabled.
      * 
@@ -71,14 +59,6 @@ class BranchConfigurationController {
         return Branch.getInstance().prefHelper_.getBool("bnc_tracking_disabled")
     }
 
-    /**
-     * Sets whether instant deep linking is enabled.
-     * This flag is used to track if the app has enabled instant deep linking.
-     */
-    fun setInstantDeepLinkingEnabled(enabled: Boolean) {
-        Branch.getInstance().prefHelper_.setBool("bnc_instant_deep_linking_enabled", enabled)
-    }
-
     /**
      * Gets whether instant deep linking is enabled.
      * 

Branch-SDK/src/main/java/io/branch/referral/ServerRequestRegisterInstall.java

@@ -62,8 +62,11 @@ public void onPreExecute() {
                 getPost().put(Defines.Jsonkey.InstallBeginServerTimeStamp.getKey(), installReferrerServerTS);
             }
 
-            JSONObject configurations = Branch.getInstance().getConfigurationController().serializeConfiguration();
-            getPost().put("operational_metrics", configurations);
+            if (Branch.getInstance() != null) {
+                JSONObject configurations = Branch.getInstance().getConfigurationController().serializeConfiguration();
+                getPost().put("operational_metrics", configurations);
+            }
+
         } catch (JSONException e) {
             BranchLogger.w("Caught JSONException " + e.getMessage());
         }