Fix wrong way of specifying shell.

Author: sharpjs

.github/workflows/build.yaml

@@ -59,7 +59,7 @@ jobs:
           -p:RepositoryCommit=${{ github.sha }}
 
       - name: Publish Version
-        pwsh: true
+        shell: pwsh
         run: |
           Add-Content $env:GITHUB_STEP_SUMMARY @"
           |            |                                   |
@@ -98,7 +98,7 @@ jobs:
           verbosity: Warning
 
       - name: Publish Coverage Summary
-        pwsh: true
+        shell: pwsh
         run: |
           Add-Content $env:GITHUB_STEP_SUMMARY @(
             "## Coverage`n"