Move jol-core to the gradle version catalog

Per @bm1549's review — the jol-core test dependency (used by the StringIndex
footprint check) now lives in gradle/libs.versions.toml under Profiling, and
internal-api references it via libs.jol.core instead of an inline coordinate.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: dougqh

gradle/libs.versions.toml

@@ -42,6 +42,7 @@ jmh = "1.37"
 # Profiling
 jmc = "8.1.0"
 jafar = "0.16.0"
+jol = "0.17"
 
 # Web & Network
 jnr-unixsocket = "0.38.25"
@@ -125,6 +126,7 @@ instrument-java = { module = "com.datadoghq:dd-instrument-java", version.ref = "
 jmc-common = { module = "org.openjdk.jmc:common", version.ref = "jmc" }
 jmc-flightrecorder = { module = "org.openjdk.jmc:flightrecorder", version.ref = "jmc" }
 jafar-tools = { module = "io.btrace:jafar-tools", version.ref = "jafar" }
+jol-core = { module = "org.openjdk.jol:jol-core", version.ref = "jol" }
 
 # Web & Network
 okio = { module = "com.datadoghq.okio:okio", version.ref = "okio" }

internal-api/build.gradle.kts

@@ -281,7 +281,7 @@ dependencies {
   testImplementation("org.junit.vintage:junit-vintage-engine:${libs.versions.junit5.get()}")
   testImplementation(libs.commons.math)
   testImplementation(libs.bundles.mockito)
-  testImplementation("org.openjdk.jol:jol-core:0.17")
+  testImplementation(libs.jol.core)
 }
 
 jmh {