promtail/client: add bot fields

[alexandre1984rj]

What this PR does / why we need it:
Adds the BotScore and BotScoreSrc fields once the Cloudflare API returns those two fields on the list of all available log fields.
https://developers.cloudflare.com/logs/logpull/requesting-logs/#fields

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

curl -s -H "X-Auth-Email: ${AUTH_EMAIL}" -H "X-Auth-Key: ${AUTH_KEY}" "https://api.cloudflare.com/client/v4/zones/${ZONE_ID}/logs/received/fields" | jq '. | to_entries[] | .key' -r | paste -sd "," -
BotScore,BotScoreSrc,CacheCacheStatus,CacheResponseBytes,CacheResponseStatus,CacheTieredFill,ClientASN,ClientCountry,ClientDeviceType,ClientIP,ClientIPClass,ClientRequestBytes,ClientRequestHost,ClientRequestMethod,ClientRequestPath,ClientRequestProtocol,ClientRequestReferer,ClientRequestURI,ClientRequestUserAgent,ClientSSLCipher,ClientSSLProtocol,ClientSrcPort,ClientXRequestedWith,Cookies,EdgeColoCode,EdgeColoID,EdgeEndTimestamp,EdgePathingOp,EdgePathingSrc,EdgePathingStatus,EdgeRateLimitAction,EdgeRateLimitID,EdgeRequestHost,EdgeResponseBytes,EdgeResponseCompressionRatio,EdgeResponseContentType,EdgeResponseStatus,EdgeServerIP,EdgeStartTimestamp,FirewallMatchesActions,FirewallMatchesRuleIDs,FirewallMatchesSources,OriginIP,OriginResponseBytes,OriginResponseHTTPExpires,OriginResponseHTTPLastModified,OriginResponseStatus,OriginResponseTime,OriginSSLProtocol,ParentRayID,RayID,RequestHeaders,ResponseHeaders,SecurityLevel,WAFAction,WAFFlags,WAFMatchedVar,WAFProfile,WAFRuleID,WAFRuleMessage,WorkerCPUTime,WorkerStatus,WorkerSubrequest,WorkerSubrequestCount,ZoneID

Checklist

• Documentation added
• Tests updated
• Is this an important fix or new feature? Add an entry in the CHANGELOG.md.
• Changes that require user attention or interaction to upgrade are documented in docs/sources/upgrading/_index.md

[CLAassistant]

All committers have signed the CLA.

[grafanabot]

./tools/diff_coverage.sh ../loki-main/test_results.txt test_results.txt ingester,distributor,querier,querier/queryrange,iter,storage,chunkenc,logql,loki

Change in test coverage per package. Green indicates 0 or positive change, red indicates that test coverage for a package fell.

+           ingester	0%
+        distributor	0%
+            querier	0%
+ querier/queryrange	0%
+               iter	0%
+            storage	0%
+           chunkenc	0%
+              logql	0%
+               loki	0%

[grafanabot]

./tools/diff_coverage.sh ../loki-main/test_results.txt test_results.txt ingester,distributor,querier,querier/queryrange,iter,storage,chunkenc,logql,loki

Change in test coverage per package. Green indicates 0 or positive change, red indicates that test coverage for a package fell.

+           ingester	0%
+        distributor	0%
+            querier	0%
+ querier/queryrange	0%
+               iter	0%
+            storage	0%
+           chunkenc	0%
+              logql	0%
-               loki	-0.6%

[KMiller-Grafana]

Thank you. The docs look good to me.

[kavirajk]

LGTM