[Flutter] Fix relative path of packages (#353)

* Fix relative path on melos.yaml

* Mention current version on CHANGELOG.md

* Remove symlink for apache license

* Address typos & relative path issues on README.md

* Ignore Flutter example app on Melos.yaml

* Remove obsolete param from Config on example app

* Do not treat info messages as critical

* Update README of Dart/Flutter packages

Revert changes on topmost README

* Update pubspec.lock

* Make dart output directory if it does not exists

* Replace continue-on-error

Resume even if previous step fails, this approach displays errors on CI summary.

* Install Protoc as part of CI workflow

* Added init-sdk as part of just bootstrap recipe which installs protobuf
* Pinned freezed to <=2.5.2

packages/flutter/example/lib/utils/config.dart

@@ -16,7 +16,6 @@ Future<Config> getConfig({
 
 extension ConfigCopyWith on Config {
   Config copyWith({
-    String? boltzUrl,
     String? liquidElectrumUrl,
     String? bitcoinElectrumUrl,
     String? workingDir,
@@ -25,7 +24,6 @@ extension ConfigCopyWith on Config {
     double? zeroConfMinFeeRate,
   }) {
     return Config(
-      boltzUrl: boltzUrl ?? this.boltzUrl,
       liquidElectrumUrl: liquidElectrumUrl ?? this.liquidElectrumUrl,
       bitcoinElectrumUrl: bitcoinElectrumUrl ?? this.bitcoinElectrumUrl,
       workingDir: workingDir ?? this.workingDir,