Accumulate multiple uses of --instrumentation_filter cli flag

### Description of the feature request:

Multiple uses of [—instrumentation_filter ](https://bazel.build/reference/command-line-reference#flag--instrumentation_filter)cli flag aren’t accumulated. This makes it difficult to have short hand config for a combination of coverage flags in a bazelrc file. e.g.,
```
build:covA --flagA --instrumentation_filter=afoo/abar,-afoo/abaz
build:covB --flagB --instrumentation_filter=bfoo/bbar,-bfoo/bbaz
build:covAB --flagA --flagB --instrumentation_filter=afoo/abar,-afoo/abaz,bfoo/bbar,-bfoo/bbaz # Filters list need to be created again
```
If --instrumentation_filter has the ability to accumulate multiple uses, having coverage for a combination of flags would have been as simple as,
```
build:covAB --config covA --config covB
```

Hence the feature being requested is to accumulate multiple uses of `--instrumentation_filter` cli flag.

### Which category does this issue belong to?

Configurability

### What underlying problem are you trying to solve with this feature?

Please see Description.

### Which operating system are you running Bazel on?

Linux

### What is the output of `bazel info release`?

release 7.2.1

### If `bazel info release` returns `development version` or `(@non-git)`, tell us how you built Bazel.

_No response_

### What's the output of `git remote get-url origin; git rev-parse HEAD` ?

_No response_

### Have you found anything relevant by searching the web?

_No response_

### Any other information, logs, or outputs that you want to share?

https://bazelbuild.slack.com/archives/CA31HN1T3/p1720168700052469

No source file or test is named. Start by searching the Bazel repository for `instrumentation_filter` and inspect how repeated command-line and bazelrc options are parsed and applied. Done means separate `--instrumentation_filter` uses combine so `--config covA --config covB` behaves like the explicitly combined filter.

Written by the indexing model from the issue text.