remove unnecessary docker_config secret from drone config

.drone.jsonnet

@@ -17,7 +17,6 @@ local PythonVersion(pyversion='3.6') = {
 
 local PipelineLint = {
   kind: 'pipeline',
-  image_pull_secrets: ['docker_config'],
   name: 'lint',
   platform: {
     os: 'linux',
@@ -58,7 +57,6 @@ local PipelineLint = {
 
 local PipelineTest = {
   kind: 'pipeline',
-  image_pull_secrets: ['docker_config'],
   name: 'test',
   platform: {
     os: 'linux',
@@ -105,7 +103,6 @@ local PipelineTest = {
 
 local PipelineSecurity = {
   kind: 'pipeline',
-  image_pull_secrets: ['docker_config'],
   name: 'security',
   platform: {
     os: 'linux',
@@ -136,7 +133,6 @@ local PipelineSecurity = {
 
 local PipelineBuildPackage = {
   kind: 'pipeline',
-  image_pull_secrets: ['docker_config'],
   name: 'build-package',
   platform: {
     os: 'linux',
@@ -200,7 +196,6 @@ local PipelineBuildPackage = {
 
 local PipelineNotifications = {
   kind: 'pipeline',
-  image_pull_secrets: ['docker_config'],
   name: 'notifications',
   platform: {
     os: 'linux',

.drone.yml

@@ -27,9 +27,6 @@ steps:
   environment:
     PY_COLORS: 1
 
-image_pull_secrets:
-- docker_config
-
 trigger:
   ref:
   - refs/heads/main
@@ -113,9 +110,6 @@ steps:
   - python38
   - python39
 
-image_pull_secrets:
-- docker_config
-
 trigger:
   ref:
   - refs/heads/main
@@ -144,9 +138,6 @@ steps:
   environment:
     PY_COLORS: 1
 
-image_pull_secrets:
-- docker_config
-
 trigger:
   ref:
   - refs/heads/main
@@ -207,9 +198,6 @@ steps:
     ref:
     - refs/tags/**
 
-image_pull_secrets:
-- docker_config
-
 trigger:
   ref:
   - refs/heads/main
@@ -245,9 +233,6 @@ steps:
     - success
     - failure
 
-image_pull_secrets:
-- docker_config
-
 trigger:
   ref:
   - refs/heads/main
@@ -261,6 +246,6 @@ depends_on:
 
 ---
 kind: signature
-hmac: 86742df377802e92b084f7c09b5cfa9fd92d2cb14840607e027ab8ff484341e5
+hmac: 423f275d3560cbd44a67f7f05e225355ea443660a74e8dbc8121dd03eac82857
 
 ...