[test-triage] uart_rx_oversample

### Hierarchy of regression failure

Block level

### Failure Description

```
UVM_ERROR @ 656811645 ps: (csr_utils_pkg.sv:457) [csr_utils::csr_rd_check] Check failed obs == exp (23012 [0x59e4] vs 46024 [0xb3c8]) Regname: uart_reg_block.val.rx reset value: 0x0
UVM_INFO @ 665361278 ps: (uart_rx_oversample_vseq.sv:37) uvm_test_top.env.virtual_sequencer [uvm_test_top.env.virtual_sequencer.uart_rx_oversample_vseq] finished run 4/6
UVM_ERROR @ 665478381 ps: (csr_utils_pkg.sv:457) [csr_utils::csr_rd_check] Check failed obs == exp (31719 [0x7be7] vs 63439 [0xf7cf]) Regname: uart_reg_block.val.rx reset value: 0x0
UVM_INFO @ 882020061 ps: (uart_rx_oversample_vseq.sv:37) uvm_test_top.env.virtual_sequencer [uvm_test_top.env.virtual_sequencer.uart_rx_oversample_vseq] finished run 5/6
UVM_INFO @ 1201077341 ps: (uart_rx_oversample_vseq.sv:37) uvm_test_top.env.virtual_sequencer [uvm_test_top.env.virtual_sequencer.uart_rx_oversample_vseq] finished run 6/6
```

84%

### Steps to Reproduce

- GitHub Revision: [50278df8b](https://github.com/lowrisc/opentitan/tree/50278df8bad5bc4ae69f0e9236b56948135febc7)
- dvsim invocation command to reproduce the failure, inclusive of build and run seeds:
./util/dvsim/dvsim.py hw/top_earlgrey/dv/chip_sim_cfg.hjson -i uart_rx_oversample --build-seed 1341560578 --fixed-seed 3644022023 --waves fsdb

### Tests with similar or related failures

- [ ] rx_oversample

Run the listed dvsim invocation at revision 50278df8b with the provided build and fixed seeds. Start by reading uart_rx_oversample_vseq.sv around line 37 and csr_utils_pkg.sv around line 457, then compare the observed and expected rx values. Done means the uart_rx_oversample test completes without the reported CSR check errors.

Written by the indexing model from the issue text.