Build failure when mvn compile

I downloaded the source zip (from https://github.com/google/s2-geometry-library-java/archive/refs/heads/master.zip) and then:

1. `mvn clean` -> OK
2. `mvn compile` ->
```
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project s2-geometry-library: Compilation failure: Compilation failure:
[ERROR] Source option 5 is no longer supported. Use 7 or later.
[ERROR] Target option 5 is no longer supported. Use 7 or later.
[ERROR] -> [Help 1]
```

Linux system:

- Linux Mint 21.3 Cinnamon
- 5.15.0-142-generic
- Intel© Core™ i7-10850H CPU @ 2.70GHz × 6

OK I found the fix. I added these 2 lines in the `properties` section of the `pom.xml` file:
`11`
`11`

Start with pom.xml and inspect the compiler configuration used by mvn compile. Compare the configured source and target levels with the Java version required by the current Maven compiler plugin, then run mvn clean and mvn compile. Done means compilation succeeds without the source or target 5 errors.

Written by the indexing model from the issue text.