re-add abseil pod with matching version to avoid ProtobufCpp conflict.

Author: ehsannas

Firestore/Example/Podfile

@@ -99,6 +99,8 @@ if is_platform(:ios)
 
     configure_local_pods()
 
+    pod 'abseil', '~> 1.20240722.0'
+
     target 'Firestore_Tests_iOS' do
       inherit! :search_paths
 
@@ -140,6 +142,8 @@ if is_platform(:osx)
 
     configure_local_pods()
 
+    pod 'abseil', '~> 1.20240722.0'
+
     target 'Firestore_Tests_macOS' do
       inherit! :search_paths
 
@@ -168,6 +172,8 @@ if is_platform(:tvos)
 
     configure_local_pods()
 
+    pod 'abseil', '~> 1.20240722.0'
+
     target 'Firestore_Tests_tvOS' do
       inherit! :search_paths