bump pxt-core to hopefully fix karma tests (#211)

* bump pxt-core to hopefully fix karma tests

* bump again

* update node version

.github/workflows/pxt-buildmain.yml

@@ -14,7 +14,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.x]
+        node-version: [18.x]
 
     steps:
       - uses: actions/checkout@v1

.github/workflows/pxt-buildpr.yml

@@ -9,7 +9,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.x]
+        node-version: [18.x]
 
     steps:
       - uses: actions/checkout@v1

.github/workflows/pxt-buildpush.yml

@@ -14,7 +14,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [8.x]
+        node-version: [18.x]
 
     steps:
       - uses: actions/checkout@v1

package.json

@@ -46,6 +46,6 @@
     },
     "dependencies": {
         "pxt-common-packages": "9.0.1",
-        "pxt-core": "7.0.18"
+        "pxt-core": "7.0.22"
     }
 }