ci: bump docker plugin to v20 (#76)

.drone.jsonnet

@@ -141,7 +141,7 @@ local PipelineBuildContainer(arch='amd64') = {
     },
     {
       name: 'dryrun',
-      image: 'thegeeklab/drone-docker:19',
+      image: 'thegeeklab/drone-docker:20',
       settings: {
         dry_run: true,
         dockerfile: 'docker/Dockerfile.' + arch,
@@ -154,7 +154,7 @@ local PipelineBuildContainer(arch='amd64') = {
     },
     {
       name: 'publish-dockerhub',
-      image: 'thegeeklab/drone-docker:19',
+      image: 'thegeeklab/drone-docker:20',
       settings: {
         auto_tag: true,
         auto_tag_suffix: arch,
@@ -170,7 +170,7 @@ local PipelineBuildContainer(arch='amd64') = {
     },
     {
       name: 'publish-quay',
-      image: 'thegeeklab/drone-docker:19',
+      image: 'thegeeklab/drone-docker:20',
       settings: {
         auto_tag: true,
         auto_tag_suffix: arch,

.drone.yml

@@ -111,7 +111,7 @@ steps:
       - make build
 
   - name: dryrun
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       dockerfile: docker/Dockerfile.amd64
       dry_run: true
@@ -123,7 +123,7 @@ steps:
       - build
 
   - name: publish-dockerhub
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       auto_tag: true
       auto_tag_suffix: amd64
@@ -141,7 +141,7 @@ steps:
       - dryrun
 
   - name: publish-quay
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       auto_tag: true
       auto_tag_suffix: amd64
@@ -183,7 +183,7 @@ steps:
       - make build
 
   - name: dryrun
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       dockerfile: docker/Dockerfile.arm64
       dry_run: true
@@ -195,7 +195,7 @@ steps:
       - build
 
   - name: publish-dockerhub
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       auto_tag: true
       auto_tag_suffix: arm64
@@ -213,7 +213,7 @@ steps:
       - dryrun
 
   - name: publish-quay
-    image: thegeeklab/drone-docker:19
+    image: thegeeklab/drone-docker:20
     settings:
       auto_tag: true
       auto_tag_suffix: arm64
@@ -381,6 +381,6 @@ depends_on:
 
 ---
 kind: signature
-hmac: ffa01b1b2f741543853ba58f761d058e2d4cbf85c9e0260be4f4273d564a8712
+hmac: 2678272f471334df973c0b9c0e8886dcf0941f5581b460b116fb48c88e7a14ba
 
 ...