Update cocoapods vesion

Author: yaroslavyaroslav

web3swift.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |spec|
     spec.name         = 'web3swift'
-    spec.version      = '2.6.3'
+    spec.version      = '2.6.4'
     spec.ios.deployment_target = "9.0"
     spec.osx.deployment_target = "10.12"
     spec.license      = { :type => 'Apache License 2.0', :file => 'LICENSE.md' }
@@ -13,9 +13,9 @@ Pod::Spec.new do |spec|
     spec.resource_bundle = { "Browser" => "Sources/web3swift/Browser/*.js" }
     spec.swift_version = '5.0'
     spec.frameworks = 'CoreImage'
-    spec.dependency 'BigInt', '== 5.2.0'
-    spec.dependency 'Starscream', '== 4.0.4'
-    spec.dependency 'CryptoSwift', '== 1.4.3'
+    spec.dependency 'BigInt', '5.2.0'
+    spec.dependency 'Starscream', '4.0.4'
+    spec.dependency 'CryptoSwift', '1.4.3'
     spec.dependency 'secp256k1.c', '~> 0.1'
-    spec.dependency 'PromiseKit', '== 6.15.3'
+    spec.dependency 'PromiseKit', '6.15.3'
 end