remove 2.19.2 test

Author: sun-jiao

.github/workflows/dart.yml

@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest ]
-        sdk: [ 2.19.2, 3.0.0, stable, beta, dev ]
+        sdk: [ 3.0.0, stable, beta, dev ]
 
     steps:
       - uses: actions/checkout@v3
@@ -34,7 +34,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest ]
-        sdk: [ 2.19.2, 3.0.0, stable, beta, dev ]
+        sdk: [ 3.0.0, stable, beta, dev ]
 
     steps:
       - uses: actions/checkout@v3
@@ -54,7 +54,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest ]
-        sdk: [ 2.19.2, 3.0.0, stable, beta, dev ]
+        sdk: [ 3.0.0, stable, beta, dev ]
 
     steps:
       - uses: actions/checkout@v3