github actions:

* upgrade upload-artifact action to v4 as v1 was deprectated long time
  go and now removed, and make sure artifact names are distinct as
  required by the new version.

* upgrade checkout action to v4 as v2 is deprecated

.github/workflows/build-posix-cmake.yml

@@ -22,7 +22,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         submodules: recursive
 
@@ -64,7 +64,7 @@ jobs:
        cp build/abc build/libabc.a staging/
 
     - name: Upload pacakge artifact
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v4
       with:
-        name: package
+        name: package-cmake-${{ matrix.os }}-${{ matrix.use_namespace }}
         path: staging/

.github/workflows/build-posix.yml

@@ -22,7 +22,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         submodules: recursive
 
@@ -60,7 +60,7 @@ jobs:
        cp abc libabc.a staging/
 
     - name: Upload pacakge artifact
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v4
       with:
-        name: package
+        name: package-posix-${{ matrix.os }}-${{ matrix.use_namespace }}
         path: staging/

.github/workflows/build-windows.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
 
     - name: Git Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         submodules: recursive
 
@@ -46,7 +46,7 @@ jobs:
        copy UpgradeLog.htm staging/
 
     - name: Upload pacakge artifact
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v4
       with:
-        name: package
+        name: package-windows
         path: staging/