UL improvements for 2-layers

This MR contains the !1928 (merged)

• Fix magnitude computation for 2-layers UL in nr_ulsch_zero_forcing_rx_2layers()
• Avoid multiple shifts in UL channel compensation
• Update the ad_shift, considering the previous improvement
• Add CI test: 3GPP G-FR1-A4-27, PUSCH Type B, 40 MHz BW, 30 kHz SCS, 2 RX Antennas Requirements Test, 2 layers

3GPP test:sudo LD_LIBRARY_PATH=. ./nr_ulsim -n5000 -b14 -I15 -i 0,1 -g C,l -t70 -u 1 -m16 -R106 -r106 -U 1,1,1,2 -W2 -y2 -z2 -s18.7 -S18.7

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SNR 18.700000: n_errors (2514/5000,10/2514,1/10,0/1) (negative CRC), false_positive 0/5000, errors_scrambling (24497578/610560000,12140901/306989568,51258/1221120,3325/122112)

SNR 18.700000: Channel BLER (5.028000e-01,3.977725e-03,1.000000e-01,0.000000e+00 Channel BER (4.012313e-02,3.954825e-02,4.197622e-02,2.722910e-02) Avg round 1.50, Eff Rate 58285.6820 bits/slot, Eff Throughput 74.83, TBS 77896 bits/slot
DMRS-PUSCH delay estimation: min 0, max 16, average 4.114500
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