fix: use correct type in GitDataClient::updateReference body

[ckolek-figs]

to fix

java.util.concurrent.CompletionException: com.spotify.github.v3.exceptions.RequestNotOkException: PATCH /repos/<org>/<repo>/git/refs/main 422: {"message":"Invalid request.\n\nFor 'properties/force', \"false\" is not a boolean.","documentation_url":"https://docs.github.com/rest/git/refs#update-a-reference","status":"422"}
	at java.base/java.util.concurrent.CompletableFuture.encodeRelay(CompletableFuture.java:368) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.completeRelay(CompletableFuture.java:377) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1152) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:510) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:2179) ~[na:na]
	at com.spotify.github.http.okhttp.OkHttpHttpClient$1.onResponse(OkHttpHttpClient.java:89) ~[github-client-0.5.2.jar:0.5.2]
	at okhttp3.internal.connection.RealCall$AsyncCall.run(RealCall.kt:519) ~[okhttp-4.12.0.jar:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) ~[na:na]
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) ~[na:na]
	at java.base/java.lang.Thread.run(Thread.java:1583) ~[na:na]
Caused by: com.spotify.github.v3.exceptions.RequestNotOkException: PATCH /repos/<org>/<repo>/git/refs/main 422: {"message":"Invalid request.\n\nFor 'properties/force', \"false\" is not a boolean.","documentation_url":"https://docs.github.com/rest/git/refs#update-a-reference","status":"422"}
	at com.spotify.github.v3.clients.GitHubClient.mapException(GitHubClient.java:1184) ~[github-client-0.5.2.jar:0.5.2]
	at com.spotify.github.v3.clients.GitHubClient.lambda$handleResponse$24(GitHubClient.java:1145) ~[github-client-0.5.2.jar:0.5.2]
	at java.base/java.util.concurrent.CompletableFuture.uniHandle(CompletableFuture.java:934) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.uniHandleStage(CompletableFuture.java:950) ~[na:na]
	at java.base/java.util.concurrent.CompletableFuture.handle(CompletableFuture.java:2372) ~[na:na]
	at com.spotify.github.v3.clients.GitHubClient.handleResponse(GitHubClient.java:1139) ~[github-client-0.5.2.jar:0.5.2]
	at com.spotify.github.v3.clients.GitHubClient.lambda$call$23(GitHubClient.java:1122) ~[github-client-0.5.2.jar:0.5.2]
	at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1150) ~[na:na]
	... 7 common frames omitted

[ckolek-figs]

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