RD: Add Xib2XiGamma DDL and DDD trigger line

Adding DDL and DDD trigger lines for the Xib- -> (Xi- -> (Lambda -> p pi) pi) Gamma decay.

These two lines are expected to benefit from our recent improvements of having the HLT1 downstream trigger lines.

BW test results: Overall +0.1MB/s

• Hlt2RD_XibmToXimGamma_XimToL0Pim_DDLDecision: 0.000113 GB/s
• Hlt2RD_XibmToXimGamma_XimToL0Pim_DDDDecision: 0.000155 GB/s

For comparison, our baseline
Hlt2RD_XibmToXimGamma_XimToL0Pim_LLLDecision gives 0.000308 GB/s.

Selection efficiency:

• Hlt2RD_XibmToXimGamma_XimToL0Pim_DDLDecision: 33%
• Hlt2RD_XibmToXimGamma_XimToL0Pim_DDDDecision: 31%

The baseline LLLDecision line gives 32% efficiency but is prescaled to 0.1, resulting in an effective efficiency of only 3%.

Note: Efficiency = (number_of_selected) / (number_of_reconstructed), requiring BKG_CAT=0.

Running over the same amount of signal MC, the number of candidates passing the trigger lines is:

• LLLDecision: 16
• DDLDecision: 440
• DDDDecision: 1120

FIY: @yihou @fibishop @adeoyang @vsvintoz