merge nix-cache build Jenkinsfiles

Signed-off-by: Jakub Sokołowski <jakub@status.im>

ci/Jenkinsfile.nix-cache

@@ -1,7 +1,5 @@
 pipeline {
-  agent {
+  agent { label params.AGENT_LABEL }
-    label 'macos'
-  }
 
   environment {
     CI_ENVIRONMENT = 'jenkins'

ci/Jenkinsfile.nix.linux

@@ -1,51 +0,0 @@
-pipeline {
-  agent { label 'linux' }
-
-  environment {
-    CI_ENVIRONMENT = 'jenkins'
-    /* we source .bash_profile to be able to use nix-store */
-    NIX_SSHOPTS = "-o StrictHostKeyChecking=no source .bash_profile;"
-    /* where our /nix/store is hosted */
-    NIX_CACHE_USER = 'nix-cache'
-    NIX_CACHE_HOST = 'master-01.do-ams3.ci.misc.statusim.net'
-    NIX_CONF_DIR = "${env.WORKSPACE}/nix"
-  }
-
-  options {
-    timestamps()
-    disableConcurrentBuilds()
-    /* Prevent Jenkins jobs from running forever */
-    timeout(time: 20, unit: 'MINUTES')
-    /* Limit builds retained */
-    buildDiscarder(logRotator(
-      numToKeepStr: '20',
-      daysToKeepStr: '30',
-    ))
-  }
-
-  stages {
-    stage('Setup') {
-      steps {
-        sh 'nix-env -i openssh'
-      }
-    }
-    stage('Build') {
-      steps {
-        sh """
-          nix build -v --no-link &&
-          nix-shell --pure --run echo
-        """
-      }
-    }
-    stage('Upload') {
-      steps {
-        sshagent(credentials: ['nix-cache-ssh']) {
-          sh """
-            find /nix/store/ -mindepth 1 -maxdepth 1 -not -name '.links' -and -not -name '*.lock' | \
-              xargs nix-copy-closure -v --to ${NIX_CACHE_USER}@${NIX_CACHE_HOST}
-          """
-        }
-      }
-    }
-  }
-}