Index command fails on Gradle multi-module project using Java toolchains inside `allprojects`

[olafurpg]

To reproduce

git clone https://github.com/olafurpg/gradle-example
cd gradle-example
git checkout 4f92b5d80c029f528873d666175553291e36f8c0
cs launch lsif-java:0.4.0 --contrib -- index
...
info: /Users/olafurpg/dev/olafurpg/gradle-example/gradlew --init-script /var/folders/mb/88qbygqj169byvv_68bw4fn80000gn/T/lsif-java5214645091470507619/java-toolchains.gradle lsifDetectJavaToolchains

BUILD SUCCESSFUL in 906ms
3 actionable tasks: 3 executed
info: /Users/olafurpg/dev/olafurpg/gradle-example/gradlew --init-script /var/folders/mb/88qbygqj169byvv_68bw4fn80000gn/T/lsif-java5214645091470507619/init-script.gradle -Porg.gradle.java.installations.auto-detect=false -Porg.gradle.java.installations.auto-download=false -Porg.gradle.java.installations.paths=/var/folders/mb/88qbygqj169byvv_68bw4fn80000gn/T/lsif-java5214645091470507619/1.8 --no-daemon clean compileTestJava
To honour the JVM settings for this build a new JVM will be forked. Please consider using the daemon: https://docs.gradle.org/6.7/userguide/gradle_daemon.html.
Daemon will be stopped at the end of the build stopping after processing

BUILD SUCCESSFUL in 5s
7 actionable tasks: 6 executed, 1 up-to-date

We see "BUILD SUCCESSFUL" but no dump.lsif file is created.

[olafurpg]

Fixed in #168