test_prometheus_log_exporter: fix wrong measurement unit expected

Unit is now bytes and not kb.

Fix this error:
```
___________________________________ test_550 ___________________________________
plex = <module 'prometheus-log-exporter' from '/home/runner/work/birdhouse-deploy/birdhouse-deploy/birdhouse/optional-components/prometheus-log-parser/config/thredds/prometheus-log-exporter.py'>
    def test_550(plex):
        log = """172.20.0.1 - - [2025-06-17T03:08:02+00:00] "GET /thredds/catalog.html HTTP/1.1" 302 0 "-" "python-requests/2.31.0" "-"
        172.20.0.1 - - [2025-06-17T03:08:02+00:00] "GET /twitcher/ows/proxy/thredds/catalog/catalog.html HTTP/1.0" 200 4200 "-" "python-requests/2.31.0" "172.20.0.1"
        172.20.0.1 - - [2025-06-17T03:08:02+00:00] "GET /thredds/catalog/catalog.html HTTP/1.1" 200 4219 "-" "python-requests/2.31.0" "-"
        172.20.0.1 - - [2025-06-17T03:08:04+00:00] "GET /twitcher/ows/proxy/thredds/wms/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc?service=WMS&version=1.3.0&request=GetCapabilities HTTP/1.1" 200 19320 "-" "python-requests/2.31.0" "-"
        172.20.0.1 - - [2025-06-17T03:08:06+00:00] "GET /twitcher/ows/proxy/thredds/wms/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc?service=WMS&version=1.3.0&request=GetCapabilities HTTP/1.1" 200 19320 "-" "python-requests/2.31.0" "-"
        172.20.0.1 - - [2025-06-17T03:08:07+00:00] "GET /twitcher/ows/proxy/thredds/wms/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc?service=WMS&version=1.3.0&request=GetCapabilities HTTP/1.1" 200 19320 "-" "python-requests/2.31.0" "-"
        192.168.0.45 - - [2025-06-17T03:08:32+00:00] "GET /twitcher/ows/proxy/thredds/dodsC/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc.dds HTTP/1.1" 200 584 "-" "oc4.9.2" "-"
        192.168.0.45 - - [2025-06-17T03:08:32+00:00] "GET /twitcher/ows/proxy/thredds/dodsC/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc.das HTTP/1.1" 200 3684 "-" "oc4.9.2" "-"
        192.168.0.45 - - [2025-06-17T03:08:32+00:00] "GET /twitcher/ows/proxy/thredds/dodsC/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc.dds HTTP/1.1" 200 584 "-" "oc4.9.2" "-"
        192.168.0.45 - - [2025-06-17T03:08:32+00:00] "GET /twitcher/ows/proxy/thredds/dodsC/birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc.dods?time,time_bnds,plev,lat,lat_bnds,lon,lon_bnds HTTP/1.1" 200 15027 "-" "oc4.9.2" "-"
        """
        for line in log.strip().splitlines():
            plex.parse_line(line.strip())

        samples = list(get_samples(plex.counter.collect(), "thredds_transfer_size_bytes"))
        assert len(samples) == 2

        s1, s2 = samples
>       assert s1.value == (584 + 3684 + 584)/1024, "Total size does not match expected value"
E       AssertionError: Total size does not match expected value
E       assert 4852.0 == (((584 + 3684) + 584) / 1024)
E        +  where 4852.0 = Sample(name='thredds_transfer_size_bytes_total', labels={'remote_addr': '192.168.0.45', 'tds_service': 'dodsC', 'datas...adal1980_r1i1p1_199101-200012.nc', 'variable': ''}, value=4852.0, timestamp=None, exemplar=None, native_histogram=None).value
tests/unit/test_prometheus_log_exporter.py:30: AssertionError
```

Author: tlvu

tests/unit/test_prometheus_log_exporter.py

@@ -27,12 +27,12 @@ def test_550(plex):
     assert len(samples) == 2
 
     s1, s2 = samples
-    assert s1.value == (584 + 3684 + 584)/1024, "Total size does not match expected value"
+    assert s1.value == 584 + 3684 + 584, "Total size does not match expected value"
     assert s1.labels["dataset"] == "birdhouse/testdata/ta_Amon_MRI-CGCM3_decadal1980_r1i1p1_199101-200012.nc"
     assert s1.labels["tds_service"] == "dodsC", "Service type does not match expected value"
     assert s1.labels["variable"] == ""
 
-    assert s2.value == 15027 / 1024
+    assert s2.value == 15027
     assert s2.labels["variable"] == "time,time_bnds,plev,lat,lat_bnds,lon,lon_bnds"