Gradle dependency `libs.guava` results in Gradle not Syncing anymore

After an upgrade whenever I try to Sync my gradle on a project I get this error:

Could not get unknown property 'guava' for extension 'libs' of type org.gradle.accessors.dm.LibrariesForLibs.

The line of code that causes the problem is:

implementation libs.guava

in the dependencies section of the build.gradle. That library is needed for ImmutableList for In App Purchase code.

You can recreate this error using the Narwal Android Studio:

1. New Project

2. Empty Views Activity

3. Language Java, Min API 21, Groovy DSL

4. Add the following to the dependencies section of the build.gradle and then SYNC the gradle:

   /* This is for the billing library we are using */
   implementation "com.android.billingclient:billing:8.0.0"
   
   /* Adverts */
   implementation 'com.google.android.gms:play-services-ads:23.3.0'
   
   /* GDPR */
   implementation "com.google.android.ump:user-messaging-platform:3.2.0"
   
   /* ImmutableList */
   implementation libs.guava
   

5. My version catalog is as follows, not edited in any way by myself:

   [versions]
   agp = "8.11.1"
   junit = "4.13.2"
   junitVersion = "1.2.1"
   espressoCore = "3.6.1"
   appcompat = "1.7.1"
   material = "1.12.0"
   activity = "1.10.1"
   constraintlayout = "2.2.1"
   
   [libraries]
   junit = { group = "junit", name = "junit", version.ref = "junit" }
   ext-junit = { group = "androidx.test.ext", name = "junit", version.ref = "junitVersion" }
   espresso-core = { group = "androidx.test.espresso", name = "espresso-core", version.ref = "espressoCore" }
   appcompat = { group = "androidx.appcompat", name = "appcompat", version.ref = "appcompat" }
   material = { group = "com.google.android.material", name = "material", version.ref = "material" }
   activity = { group = "androidx.activity", name = "activity", version.ref = "activity" }
   constraintlayout = { group = "androidx.constraintlayout", name = "constraintlayout", version.ref = "constraintlayout" }
   
   [plugins]
   android-application = { id = "com.android.application", version.ref = "agp" }
   

You try to add the dependency guava from your version catalog with this:

implementation libs.guava

But your version catalog doesn't have a guava dependency defined in the [libraries] section. Hence the error

Could not get unknown property 'guava' for extension 'libs' of type org.gradle.accessors.dm.LibrariesForLibs.

Just add a new entry guava there, with the desired group, name and version - just like the other entries. The version should be specified as a reference to an appropriately named entry in the [versions] block.