Adopt NSIS 3.0 (#2248)

.github/workflows/build.yaml

@@ -120,10 +120,6 @@ jobs:
             ${{ runner.os }}-64-${{ matrix.configuration }}-
             ${{ runner.os }}-64-
 
-      - name: Install windows dependencies
-        if: runner.os == 'Windows'
-        run: choco install nsis-unicode
-
       - name: Determine source branch
         id: which-branch
         uses: secondlife/viewer-build-util/which-branch@v2

indra/newview/installers/windows/installer_template.nsi

@@ -32,6 +32,7 @@ SetCompressor /solid lzma	# Compress whole installer as one block
 SetDatablockOptimize off	# Only saves us 0.1%, not worth it
 XPStyle on                  # Add an XP manifest to the installer
 RequestExecutionLevel admin	# For when we write to Program Files
+Unicode true                # Enable unicode support
 
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