update podspec

Author: zmgl

web3swift.podspec

@@ -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', '1.5.1'
-    spec.dependency 'secp256k1.c', '0.1.2'
-    spec.dependency 'PromiseKit', '6.15.3'
+    spec.dependency 'BigInt'
+    spec.dependency 'Starscream'
+    spec.dependency 'CryptoSwift'
+    spec.dependency 'secp256k1.c'
+    spec.dependency 'PromiseKit'
 end