[!480] - Resolve "Publish snapshots on sonatype central instead of private gitlab repo"

Closes #593

Author: agilelab-tmnd1991

README.md

@@ -9,8 +9,8 @@
 
 ## Install
 
-Wasp final releases are published to maven central through sonatype. 
-Snapshot releases are published to a private Gitlab Registry:
+Wasp final releases are published to maven central through sonatype, snapshot releases are published to sonatype maven-snapshots. 
+
 
 ```scala
 libraryDependencies += "it.agilelab" %% "wasp-consumers-spark" % "3.0.1"
@@ -19,17 +19,7 @@ libraryDependencies += "it.agilelab" %% "wasp-consumers-spark" % "3.0.1"
 or (for snapshots)
 
 ```scala
-val gitlabHost             = "gitlab.com"
-val gitlabRegistryEndpoint = s"https://${gitlabHost}/api/v4/projects/3748812/packages/maven"
-
-ThisBuild / resolvers += "gitlab" at gitlabRegistryEndpoint
-ThisBuild / credentials += Credentials(
-  "GitLab Packages Registry",
-  gitlabHost,
-  "<token name>",
-  "<token>"
-)
-
+ThisBuild / resolvers += "Sonatype Central Snapshots" at "https://central.sonatype.com/repository/maven-snapshots"
 libraryDependencies += "it.agilelab" %% "wasp-consumers-spark" % "3.1.0-SNAPSHOT"
 ```
 To download Wasp snapshot releases you need a personal access token or a project access token with read_api scope and role Developer to GitLab Wasp project. 

project/Settings.scala

@@ -115,19 +115,10 @@ class BasicSettings(
     System.getenv("SONATYPE_PASSWORD")
   )
 
-  val gitlabHost             = "gitlab.com"
-  val gitlabRegistryEndpoint = s"https://${gitlabHost}/api/v4/projects/3748812/packages/maven"
-  val gitlabCredentials = Credentials(
-    "GitLab Packages Registry",
-    gitlabHost,
-    "gitlab-ci-token",
-    System.getenv().get("CI_JOB_TOKEN")
-  )
-
   lazy val publishSettings = Seq(
-    publishTo := { if (isSnapshot.value) Some("GitLab" at gitlabRegistryEndpoint) else localStaging.value },
+    publishTo := { if (isSnapshot.value) Some("central-snapshots" at centralSnapshots) else localStaging.value },
     publishMavenStyle := true,
-    credentials ++= Seq(sonatypeCentralCredentials, gitlabCredentials),
+    credentials ++= Seq(sonatypeCentralCredentials),
     pgpPassphrase := Option(System.getenv().get("PGP_PASSPHRASE")).map(_.toCharArray),
     Global / useGpg := false
   )