Build the release launcher with cs bootstrap --assembly

The --standalone launcher keeps dependency jars nested inside the
launcher jar, so the Kotlin compiler cannot locate
extensions/compiler-cli-root.xml on disk and Kotlin indexing fails with
"Unable to find extension point configuration". An --assembly
launcher merges the dependencies into a single jar, which works.

Amp-Thread-ID: https://ampcode.com/threads/T-01a1aac9-e7b5-72af-ad93-8f4a2a058fac
Co-authored-by: Amp <amp@ampcode.com>

Author: christoph-sg

.github/workflows/release-cli.yaml

@@ -54,7 +54,7 @@ jobs:
           done
 
           cs bootstrap \
-            --standalone \
+            --assembly \
             -o scip-java \
             "$ARTIFACT" \
             --main org.scip_code.scip_java.ScipJava

docs/getting-started.md

@@ -90,7 +90,7 @@ binary.
 # macOS/Linux
 curl -fLo coursier https://git.io/coursier-cli \
   && chmod +x coursier \
-  && ./coursier bootstrap --standalone -o scip-java org.scip-code:scip-java:@STABLE_VERSION@ --main org.scip_code.scip_java.ScipJava
+  && ./coursier bootstrap --assembly -o scip-java org.scip-code:scip-java:@STABLE_VERSION@ --main org.scip_code.scip_java.ScipJava
 ./scip-java --help
 ```