ci: update actions versions and usage

* bump actions/checkout to v3
* explicitly checkout modflow6 develop branch
* run build_nightly.py with shell: pwsh on Windows

.github/workflows/nightly-build-intel.yml

@@ -43,7 +43,7 @@ jobs:
 
  steps:
  - name: Checkout repo
- uses: actions/checkout@v2.3.4
+ uses: actions/checkout@v3
 
  - name: Setup Python
  uses: actions/[email protected]
@@ -63,6 +63,7 @@ jobs:
  with:
  repository: MODFLOW-USGS/modflow6
  path: modflow6
+ ref: develop
 
  - name: Update flopy classes
  working-directory: modflow6/autotest
@@ -78,8 +79,8 @@ jobs:
  - name: Build and zip (Windows)
  if: runner.os == 'Windows'
  working-directory: modflow6/distribution
+ shell: pwsh
  run: |
- export PATH="/C/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Tools/MSVC/14.33.31629/bin/Hostx64/x64":$PATH
  python build_nightly.py
 
  - name: Move the build zip file

.github/workflows/nightly-build.yml

@@ -55,6 +55,7 @@ jobs:
  with:
  repository: MODFLOW-USGS/modflow6
  path: modflow6
+ ref: develop
 
  - name: Update flopy classes
  working-directory: modflow6/autotest

.github/workflows/nightly-distribution.yml

@@ -79,6 +79,7 @@ jobs:
  with:
  repository: MODFLOW-USGS/modflow6
  path: modflow6
+ ref: develop
 
  - name: Checkout modflow6 examples
  uses: actions/checkout@v3