Tempo 2.0: Config Cleanup

[joe-elliott]

What this PR does:
This is a config cleanup pass to prepare for 2.0. The following changes were made to config:

Defaults Updated
Settings listed with new defaults. These defaults were changed to work better with the new Parquet backend.

query_frontend:
    max_oustanding_per_tenant: 2000
    search:
        concurrent_jobs: 1000
        target_bytes_per_job: 104857600
        max_duration: 168h
        query_ingesters_until: 30m
    trace_by_id:
        query_shards: 50
querier:
    max_concurrent_queries: 20
    search:
        prefer_self: 10
ingester:
    concurrent_flushes: 4
    max_block_duration: 30m
    max_block_bytes: 524288000
storage:
    trace:
        pool:
            max_workers: 400
            queue_depth: 20000
        search:
            read_buffer_count: 32
            read_buffer_size_bytes: 1048576

Renamed/Moved/Removed Config

query_frontend:
    query_shards: // removed. use trace_by_id.query_shards
querier:
    query_timeout: // removed. use trace_by_id.query_timeout
compactor:
    compaction:
        chunk_size_bytes:   // renamed to v2_in_buffer_bytes
        flush_size_bytes:     // renamed to v2_out_buffer_bytes
        iterator_buffer_size: // renamed to v2_prefetch_traces_count
ingester:
    use_flatbuffer_search:   // removed. automatically set based on block type
storage:
    wal:
        encoding:  // renamed to v2_encoding
        version:     // removed and pinned to block.version
    block:
        index_downsample_bytes:  // renamed to v2_index_downsample_bytes
        index_page_size_bytes:      // renamed to v2_index_page_size_bytes
        encoding:                  	    // renamed to v2_encoding
        row_group_size_bytes:       // renamed to parquet_row_group_size_bytes

As part of the removing useFlatBufferSearch and requiring the wal and block Version to be the same the tests in ./modules/ingester had to be heavily reworked. This is b/c they were written for flatbuffer/v2 wal and they have now been updated to use the current block type for the wal (vparquet). During this process the following bugs were found and corrected:

• SearchTags/TagValues was not working on the parquet headblock/completing blocks
• When replaying a parquet wal block we were double counting total objects

Finally, I would still like to remove search_enabled and metrics_generator_enabled but I intend to do that in a future PR as this has gotten quite large.

Checklist

• Tests updated
• Documentation added
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]