Remove redundant section about custom workers

Author: giordano

docs/src/advanced.md

@@ -80,7 +80,7 @@ The `init_code` is evaluated in each test's sandbox module, so all definitions a
 
 ## Custom Workers
 
-For tests that require specific environment variables or Julia flags, you can use the `test_worker` keyword argument to assign tests to custom workers:
+For tests that require specific environment variables or Julia flags, you can use the `test_worker` keyword argument to [`runtests`](@ref) to assign tests to custom workers:
 
 ```julia
 using ParallelTestRunner
@@ -137,25 +137,6 @@ runtests(MyPackage, args)
 
 Custom flags are stored in the `custom` field of the `ParsedArgs` object, with values of `nothing` (not set) or `Some(value)` (set, with optional value).
 
-## Manual Worker Management
-
-For advanced use cases, you can manually create workers:
-
-```julia
-using ParallelTestRunner
-
-# Add a single worker with custom configuration
-worker = addworker(
-    env = ["CUSTOM_VAR" => "value"],
-    exeflags = ["--check-bounds=no"]
-)
-
-# Add multiple workers
-workers = addworkers(4; env = ["THREADS" => "1"])
-```
-
-Workers created this way can be used with the `test_worker` function or for other distributed computing tasks.
-
 ### Interactive use
 
 Arguments can also be passed via the standard `Pkg.test` interface for interactive control. For example, here is how we could run the subset of tests that start with the testset name "MyTestsetA" in i) verbose mode, and ii) with default threading enabled: