fixed displayName typo [skip ci]

Author: JohnstonCode

build.yml

@@ -21,7 +21,7 @@ jobs:
         inputs:
           verbose: false
       - task: Npm@1
-        displayname: 'Lint check'
+        displayName: 'Lint check'
         inputs:
           command: custom
           verbose: false
@@ -56,7 +56,7 @@ jobs:
         inputs:
           verbose: false
       - task: Npm@1
-        displayname: 'Lint check'
+        displayName: 'Lint check'
         inputs:
           command: custom
           verbose: false
@@ -91,7 +91,7 @@ jobs:
         inputs:
           verbose: false
       - task: Npm@1
-        displayname: 'Lint check'
+        displayName: 'Lint check'
         inputs:
           command: custom
           verbose: false