add serial variable to playbooks

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

ansible/mainnet.yml

@@ -11,6 +11,7 @@
 
 - name: Configure network mainnet bootnodes
   become: true
+  serial: '{{ serial|default(1) }}'
   hosts: 'nimbus-mainnet-small'
   vars:
     # WARNING: Since these are Eth 2 bootnodes we need to keep the keys and IPs unchanged.
@@ -29,6 +30,7 @@
 
 - name: Deploy mainnet linux beacon nodes
   become: true
+  serial: '{{ serial|default(1) }}'
   hosts: nimbus-mainnet-metal
   roles:
     - { role: redirect-ports,               tags: [ redirect-ports ] }
@@ -43,6 +45,7 @@
 
 - name: Configure periodic puging of nodes DBs
   become: true
+  serial: '{{ serial|default(1) }}'
   hosts: nimbus-mainnet-metal
   tasks:
     - include_role: name=nimbus-db-purge

ansible/prater.yml

@@ -13,6 +13,7 @@
   become: true
   # To avoid clashing/duplicate validators.
   any_errors_fatal: true
+  serial: '{{ serial|default(1) }}'
   hosts:
     - nimbus-prater-stable
     - nimbus-prater-testing
@@ -29,6 +30,7 @@
 
 - name: Deploy mainnet linux beacon nodes
   become: true
+  serial: '{{ serial|default(1) }}'
   hosts: nimbus-prater-metal
   roles:
     - { role: redirect-ports,    tags: [ redirect-ports ] }
@@ -44,6 +46,7 @@
 - name: Deploy prater Windows beacon nodes
   become: true
   become_user: 'admin'
+  serial: '{{ serial|default(1) }}'
   hosts: nimbus-prater-windows
   fact_path: 'C:/ansible/facts.d'
   roles:
@@ -58,6 +61,7 @@
 
 - name: Deploy prater macOS beacon nodes
   become: true
+  serial: '{{ serial|default(1) }}'
   hosts: nimbus-prater-macos
   roles:
     - { role: get-geth-api-urls, tags: [ get-geth-api-urls ] }

ansible/requirements.yml

@@ -46,17 +46,17 @@
 
 - name: infra-role-beacon-node-linux
   src: git@github.com:status-im/infra-role-beacon-node-linux.git
-  version: a573ab89f2a75a7c80ba98e254b26644b9eb2fb2
+  version: 27243637e56cb3c3ff83832acbb60cc772f9a7f9
   scm: git
 
 - name: infra-role-beacon-node-windows
   src: git@github.com:status-im/infra-role-beacon-node-windows.git
-  version: f7b8578873dff723784aca9bd550f1f0dc32a9c1
+  version: 48f5c10dca51e053f422913ed835132e3d96d87c
   scm: git
 
 - name: infra-role-beacon-node-macos
   src: git@github.com:status-im/infra-role-beacon-node-macos.git
-  version: 159f8e6bf078e33a7901ba03c7c4225093e23d86
+  version: 11da856632fb66b79c7229f82b90aa7fc2da08c6
   scm: git
 
 - name: infra-role-nimbus-eth1